The Antec 300 will fit everything but its going to be extremely cramped with that 1000W. Honestly, unless your using 3xSLI/CFX you wont need it. If you plan on just dual GPUs get a 750W. This will save you $100 on just the PSU and $150-200 on an additional GPU. In my opinion anything over 2 GPUs is overkill.
The Corsair RAM is expensive and has a high profile which could get in the way of your HSF. I found you some cheaper, quality RAM that will do exactly what you need.
Everything looks good. You are going to want a full tower case if you plan on using 3xSLI/CFX. And I would also suggest waiting to buy a GPU until the ATI 5870 is released. It will certainly drop prices on current models in time or you can buy the 5870.
5870 is supposed to be insane, like 2 4890's in one card while staying cool. I've read a review, I think on Anandtech, were 1 5870 was powering 4 monitors with ease while playing a single game!
PS: If you plan on watching Blu-Ray in the future you are going to want a better monitor. The Acer brand will not support true 1080p which will handicap Blu-Ray. LG is great, Samsung is nice too.
If your just going to game and surf and have no intentions on Blu-Ray (you have a PS3 or something) stick with the monitor you have chosen. For the price, you can't go wrong. I wouldn't buy a Blu-Ray player for your rig anytime soon though. They need to improve the drives a lot. But this will "future proof" your monitor for quite some time.
Any suggestions for power supplies? Obviously I want something SLI ready but I'd also like to get a modular PSU for cable management. Seems like the GTX 295 requires 2 connectors, a 6 pin and 8 pin, and I've read a lot of people saying it should be a DEDICATED 8 pin, no adapters. So does this mean I would need 2 x 6 pin and 2 x 8 pin? I'm having a hard time finding a PSU with enough wattage that fits those requirements. This is my first time considering running SLI so maybe I'm way off base.
Appreciate the answers. I'm looking into a 1080p monitor now. Seems like there are a handful of ASUS monitors on newegg with great reviews at a decent price, but to be honest it's not THAT big of a deal for me. I'm more concerned with playing any game I want at max settings at max resolution.
EDIT: I should mention I currently have an Antec p182 case. It's a great case and the Antec 300 might be a downgrade, but this thing is so damn heavy and large it gets kind of frustrating every time I need to move it. But it does keep my components cool, so maybe I should just stick with this case?