E7400 for now, i7 next year? Advice needed

Since I am always trying to decide what to do, I wanted to ask if this is a reasonable choice. I want to upgrade, but I think the time is not right with the i7s being so new.

So, I was thinking maybe buying an E7400, which is the fastest processor I can put on my 1066 FSB mobo (Asus P5B - I can put all socket 775 CPUs, but they would be bottlenecked, right?) and maybe waiting another year or so (I think the E7400 will last me that long at least) to make the right i7 choice/upgrade, especially at a time when quad cores will be fully supported by all games (I am mostly interested in games, but I am not that big on eye candy).

Also I want to ask if the E6400 I have now uses the same power amounts as the E7400, so I won't have to change my chieftec 400W PSU as well, considering I don't know what I'll be needing next year.

Please don't tell me to overclock, I have no idea how to do it and even if I do use the tutorials, potential trouble will leave me hanging (I actually tried it once, but I reset it immediately...it was scary).

My system in short:
E6400
ATi 4850
Asus P5B mobo
2 GB RAM PC2-5400
Chieftec 400W PSU
WD 250 GB Sata II

Will it play games decently (medium detail, 1440x900, around 40-50 fps) for a year with a E7400? My E6400 is really starting to show its age and in games, when it is needed, my fps drop (physics in Dead Space come to mind - 50-60 throughout the game, 20 when monster's bodies break in pieces).

PS: I am sorry if I am tiring anyone. I am really at a loss about what to do. I must have made around 5 topics and I still haven't decided.