I've been monitoring this thread fairly closely - I dig building computers :) - and the dichotomy that I frequently see when it comes to building gaming rigs has shown up here. Buy all that you can afford now vs. buy what the software needs/can use. Both are completely valid. You simply need to decide what is best for you.
Vaygrent is right. The capabilities of software in a year will increase dramatically over their capabilities right now. Nature of the beast. He is also VERY right that adding an SSD is a great idea. I actually have two in mine - one 60GB for the OS (you can get away with a 30GB one for the OS for those that are more familiar with Windows, page files, etc, but for most folks I'd recommend 60GB), and one other one for GW2 and any other apps that I want to have fast response times with. I then have a 500GB traditional disk for my data and media. This type of setup provides a number of benefits:
- Screaming fast startup times
- Reduced loading screen times for gaming
- Distribution of work across multiple disks so that your OS, games, and media aren't all fighting for the same read/write requests
- Mild system integrity benefits; you can keep a backup image of your OS disk on your media drive, plus if either your media/gaming drives die, you still have your main OS disk to run the system against.
At a minimum, add one SSD to your system.
Arowefell is also right in that the cost/benefit analysis of 16GB vs 32GB RAM right now is a bit out of whack. To be clear, RAM is pretty cheap right now. You can find 16GB of pretty good, name brand, gaming-quality RAM out there for $45-60 for 16GB. That being said, if you have 16GB of RAM in your system, it is unlikely that you will get your money's worth if you add another 16GB of RAM right now. May as well keep the cash in your pocket and then add more if you need/want it down the road when the parts are even cheaper. This is especially true considering that RAM is quite possibly the easiest possible part to add/replace in a computer. Also know that, considering the system you're currently spec'ing out, GW2 will become it's own bottleneck. The engine itself can only process data so fast, regardless of how many horses you throw at it, and there are numerous anecdotal reports of folks building screaming machines only to see few/no tangible benefits as far as rendering the environment/players/NPC's surrounding them. For comparative purposes, I'm running a current-gen i5 with a 6850 and 16gb RAM, and during a dragon kill, fraps running, and a virtual machine running at the same time, I never dropped below 28FPS and consistently stayed at 30-40. With only the game running, I pretty much run 60+ FPS in most world/instanced environments in all but the most crazy situations.
As to your questions re: fan vs. liquid cooling. I've done both, and I live in a desert. And both cooling systems have been through the crap situation of having the AC die in the hottest month of the year. The liquid cooling systems were only 2-3 degrees cooler than my traditional cooling systems at any given time. In the interest of full disclosure, I always run maximum case fans. As long as you have good push/pull airflow set up with in your box, traditional cooling systems should be fine and don't run the risk of coolant hose rupture. The biggest benefit I see in most liquid cooling systems is reduced noise.
Although I can and have built my own systems, I have also used Cyberpower four times over the past four years for various purposes. Sometimes they are cheaper, sometimes they're not. Right now, they're batting .500 as far as providing me successful systems. The two gaming rigs I had them build for me have been rock solid and happened to come with Gigabyte/MSI components (frequently they use cheaper Powercolor video cards, which I don't recommend). One computer came DOA and I had to send back for a refund. One computer that was built for data integrity was a cluster of a failure and was a nightmare to deal with. In short, my good experiences with them have been great. My bad experiences with them have been the complete polar opposite. It's a bit of a crapshoot.