To be fair if you already have a 3.4Ghz Core2Duo you're just looking for reasons to upgrade, you won't gain hardly anything since you game at what, 1680x1050?
General Windows performance probably won't gain a noticeable increase in speed, maybe you should ask yourself if you do enough Photoshop/Video encoding to justify getting another 600 or so Mhz.
I'll be waiting for the new range of Quads myself, there is no reason for me to upgrade, if I was that fussed for an increase in Photoshop/Video editing I'd go Q6600, as for gaming whether I'm at 3Ghz or 4.4Ghz I'm not gaining any FPS at 1920x1080.
Of course it will, games are going to be GPU limited for some time yet.
You WILL notice a difference betwenn 3Ghz and 4.4Ghz, sorry but get real, that's a massive 1.4Ghz increase. If you don't notice any sort of increase or difference you'd have to be blind or just plain retarded.
You may think differently when the new quads come and they're not what you expected.
(Read the Intel Delay thread)