Well, that would not be a part of this topic then, as this topic is about playing games on a mac.

http://antivirus.about.com/od/macintoshresource/tp/macvirusfaqs.htm

EDIT: And If About.com is not good enough for you (understandable), then here:

http://www.sophos.com/pressoffice/news/articles/2006/02/macosxleap.html

AND

http://www.sophos.com/security/analyses/viruses-and-spyware/search-results/?search=Mac&action=search&x=0&y=0

This states that Macs cannot get viruses, which, if you're online, which most gamers play online, and most logical people would browse on the same systems, saying that macs can't get viruses is simply not true.

someone will have to explain to me sometime why vista gets so much hate. I have used it, though I don't own it, didn't have any problems. Asked family members who are knowledgeable why it gets so much hate and they don't know. I have a neighbor who bought a cheapo pc with vista and games on it with a dual core 1.6 ghz processor, yes 1.6, and has no problems.

ah yes ive read of this one, never seen it in the wild never heard about it in the wild, from what i know sophos found a pile of test viruses and old exploits, but none were ever out in wild replicating, and used this info to scare people into buying their product.

also leap a only effects avery small number of mac useres, those using 10.4.1-10.4.3 current os is 10.5.5 (edit looking this up also apears to be proof of concept they won money for developing it at a hackers convention cool)

on your last link over half of those are pre osx bugs, and have no effect on current os, one was an outlook bug, and unless you have really old office 3 versions ago without patches to be exact your fine 

Mac/nVIR-A os9 (so does not work on new macs) i actualy infected a computer on perpose with this bug...

heh its a funny one, kinda creepy if you dont know its infected

Mac/Cowhand-A and its varients have been proven to be in lab proof of concept 

there are a few in that list that are windows exploits that effect the mac address 

very nice list though they are only missing 2 or three proof of concept and a few really old mac bugs from around os 7 

still no listing of an osx bug in the wild 

As you are posting this question on a video game related forum, I can only assume that you are in fact interested in playing video games.

Buy a computer with Windows as with it you will gain the widest commercial game selection.

Current imacs? do not buy the 20". It packs an underpowered screen that can't show millions of colors - it uses dithering to simulate them. Go for the 24" to get the real deal. I have a 24" at home and use a 20" at work and the difference in the quality screen is considerable. Of the current models only the top of the line packs a pseudo-acceptable gpu for gaming but the sucker is like 1900$. Ouch.

Apple usually upgrades imac 1-2 months after a laptop upgrade (which is happening tomorrow), so unless you were in a hurry I'd wait and get a fresh one. Up to you. Also, buy another 2gb ram stick yourself and upgrade as soon as the box hits your house - do NOT order the extra ram from Apple, you've been warned.

Yeah, Mac OS X rocks whatever version of windows. If you still care about gaming you can use bootcamp (it comes with the OS) to create a windows partition to boot from alternatively to play your games. It's not the same as having them native, specially since windows can't access the contents on the mac os partition. Well, you can as long you shell out 40$ for the HFS drivers. Alternatively you can use something like vmware fusion to run windows inside mac os but it incurs in a performance hit.

My opinion? I've had a 24" for a year and it's terrific: the screen is great, it runs pretty much silent and the one-box approach kills a lot of clutter around your computer area. Oh yeah, Mac OS X rocks, did I mention that already?.

Negatives I've noticed? The OS is damn lazy about ramping up fan speed so it can get really hot - get smcFanControl (free) to take care of that. Also, the screen is bright as fuck - I use a (free) utility, Brightness Control, to moderate it. Whenever I'm watching a movie or using color-critical apps I disable it. Oh, I forgot: video-conference through MSN is a rocky issue - your only option is aMSN and I wonder how the hell they coded it, but it's sluggishly painful to use. Other IM protocols (including raw-text MSN) have better support - there's a little wonder called Adium, google it.

edit: viruses for mac OS X are practically non-existant. Virus makers tend to not care =). Trojans however DO exist - beware of what applications you download from the internet, just because it's a mac OS X machine doesn't mean people can't build a malicious application and trojan it as miley_cirus_naked.app

edit2: QuickSilver. It's free and it's the best.thing.ever

If you're going for gaming then XP is fine and stable syste... Linux doesn't suck, but it'll be likely target as some of the distros become more popular with the common folk. The Macs are not worth your money as a gaming machine... if you like Apple get one otherwise it's pointless to spend extra money on a system when you're just going to have to use bootcamp to run windows anyway. As for Viruses on Macs... I'm surprised that there isn't a effort to take advantage of the idiots who use Macs. I run across techs like our own goddog every now and then, but most of these users are morons that make my grandmother look like a network tech (to be fair she did figure out how to set up a home network all on her own with three computer).