I am a Hellgate founder myself!
I have to say, it was quite the game for the first dozen hours or so. The graphics are stellar and my machine (only on a 4800+ processor, 3 gigs ram, Vista) runs it exceptionally. Then again, I can run Crysis, so that kinda ruins the point of this game.
I don't like the grind much, but the patches that are upcoming (despite the game switching to a Korean developer) should make the game at least comparable to Diablo II.
Now, Mythos is much better overall, but don't expect to play that for a while. They shut down the beta until they get the developer thing all figured out. That game is MUCH more polished and more fun to play, but you can't beat 20$ for Hellgate to try out that new DirectX 10 video card!