If you're considering buying an Intel Mac, I thought I'd post a few comments about the suitability of the various models for gaming. These are my personal opinions, so don't take them as gospel - do your own research as to which MacIntel would be the most suitable in your situation! But these guidelines might help you focus a little better as it can be quite confusing if you're not very familiar with computers and gaming. And I do know of people who've bought the wrong Mac because they made some false assumptions - Apple love to tell you how great their computers are, but don't emphasise the limitations...
Bear in mind that no Intel Mac can play a classic Mac game, which means any game that only runs in Mac OS 9 or earlier (or in the PPC OS X Classic Mode) - this rules out every Tomb Raider up to Last Revelation (TR4)! The only software you're able to run in OS X on an Intel Mac (apart from software designed to run on it) is PPC OS X software, which is software designed to run in the PowerPC version of OS X (Cocoa or Carbon software). But this runs in the Rosetta translator and takes a big speed hit so don't expect too much. For games, look for software and updates labelled 'Universal', which is written to run in OS X in both PPC and Intel Macs. Most Mac game companies are working on Universal updaters for some of their older games, so check them out (an American McGee's Alice Universal patch has just been released by Aspyr - see my previous post!)
A further consideration is that all Intel Macs are able to be booted into Windows XP. To do this requires you to buy a copy of Windows XP Service Pack 2 and download Apple's Boot Camp software to run the install. Boot Camp updates the Mac's BootROM to allow the Windows boot, and also updates the Windows hardware drivers to be compatible with Mac hardware. This allows you to boot into XP and run Windows games on your Mac utilising the graphics hardware and DirectX - generally you'll experience much the same compatibility and performance as you would running a standard Win XP PC with similar specifications! Note that virtualisation software such as Parallels is yet to support gaming, but they intend to include support in a future update. Parallels already supports running a virtual machine from a Boot Camp partition though, so you can install Boot Camp for PC gaming use first, then use Parallels with the same Win XP install for other Windows software!
The addition of an Elgato EyeTV Hybrid video input device would allow an Intel Mac to be used as a display for a games console instead of a TV, as well as doubling as a TV and digital video recorder. The EyeTV Hybrid contains an analogue TV receiver, as well as an SD and HD digital TV receiver (depending on your regional compatibility) so could conceivably replace your TV and digital set top box, thus turning a Mac into a digital TV and a hard drive DVD recorder as well! None of the other EyeTV models are suitable for games consoles due to input lags so be sure to choose the Hybrid for this purpose.
The following comments on individual models refer to the currently available models at March 2007!
Mac mini - A capable little Mac for general use, but suitable only for lightweight gaming use due to its Intel integrated graphics (which shares its RAM with the system). I've heard that it's just possible to play some of the more intensive games on it, but only with all the game graphics options turned off. Undemanding casual gaming only, and max out the RAM for best performance.
MacBook - Again, a capable general purpose computer but as it has Intel integrated graphics this is also only recommended for undemanding casual gaming, best with maxed out RAM.
MacBook Pro - More powerful than the MacBook, and with a dedicated graphics chip, so capable of running more demanding games. If you're serious, choose a model with the 2.33GHz Core 2 Duo processor and Radeon X1600 256MB graphics! A top end MacBook Pro has gaming potential for most but the more demanding games today.
iMac - Varies a lot depending on the model, from very ordinary to very good. The base model 17" has integrated graphics so my comments on the Mac mini and MacBook apply here as well. All the others have dedicated graphics chips, and gaming performance improves as you go up the list. The top end 24" iMac optioned with the 2.33GHz Core 2 Duo, GeForce 7600 GT 256MB graphics, and 2-3GB of RAM, is a quite capable gaming machine for anything except the most intensive games. The 20" when optioned up to the 2.33 GHz Core 2 Duo, Radeon X1600 256MB graphics, and 2-3GB RAM is also a capable gaming machine for most purposes, the most significant difference being the screen size. The only limitation with these is the fairly slow response times of the monitors (around 14ms) so if possible take a DVD movie into an Apple Store or Apple Centre and run it in your iMac of choice to see whether motion blur may be a problem for you. But for most of us either an optioned 20" or 24" is a good choice as a general purpose Mac with decent gaming capabilities. One of these iMacs would also make a nice PC game machine for the average gamer! If you want to use it as an entertainment centre in your living area then the 24" (61cm) 16:10 screen is a quite decent size for longer distance viewing, but be sure to check it out in an Apple Store if possible before deciding.
Mac Pro - Option this up and you're in gamer's heaven, Mac or PC! At a cost... (Unless you're one of those gamers who overclocks everything, uses liquid nitrogen to cool it, and can't do with less than twin high end graphics cards, in which case build your own PC...) For the rest of us, don't bother with the insanely expensive nVidia Quadro FX 4500 graphics option, rather go for the ATI X1900 XT 512MB graphics which is almost as good for gaming but far, far cheaper. The multiple GeForce 7300 GT options are intended for general multiple screen use, not games, so don't bother. The twin 3GHz dual core Intel Xeon processor option is also expensive and 4 processor cores won't be much use in games yet, so the 2.66GHz option could be quite adequate and a lot cheaper. There's room for 2 Superdrives, up to 4x 750GB hard drives, and 16GB RAM, so if you love upgrading and have a very generous bank manager, this gives you plenty of scope ;)
LCD Monitors - if you're running a Mac Pro you'll need a good monitor. Apple monitors have good colour and contrast but a fairly slow response time of around 14ms. That is, the time for the screen elements to respond to colour changes, which very roughly equates to refresh rates in the old CRT monitors. Apple monitors would be fine for the average person (albeit a little expensive), but serious gamers will want to buy something a lot faster, down around 2ms response time or less, to reduce motion blur as much as possible (this is also relevant when playing movies). There are some good fast LCD monitors around now which deliver high performance with good colour and contrast, so check them out in a store which displays them running to see if they'd suit you!