Lots of Upgrade Questions

Looking to upgrade my current rig. Here's my current rig (the one I'm using right this second):

ASUS A8N-SLI Deluxe
AMD Athlon 64 3700+ San Diego
Corsair HX520w
2GB G.Skill DDR
EVGA 7800GT
Western Digital 250GB Caviar
ASUS 18x DVD Burner
X-Fi Xtrememusic
all bundled inside my nice, big and cool Lian-Li PC61

I'm looking to replace my motherboard, processor, video card and RAM. I'm leaning towards the following:

Intel Q6600
Gigabyte GA-P35-DS3L Mobo
4GB G.Skill DDR2 1066 (PC2 8500)
MSI OC 8800GT

Here are my questions:

1) Can my Corsair power supply handle the new additions?
2) Is the Q6600 the way to go, or an E8400?
3) How long until the 9800's are released by nVidia?
4) Do we expect a price drop in the 8800GT at that time?
5) I do plan to OC this thing, but I'm a first timer...never OC'd before. Not sure if my RAM is qualified for that or not. Your thoughts?
6) Overall, any changes recommended to this upgrade?

1) The corsair should be good.
2) Assuming your use is for games, then I would take the E8400. Few games can take advantage of more than 2 cores. FSX is an exception. By the time that changes, nehalem will be upon us,a and all things will change. I would today take the higher clock speed of the E8400.
3) About two weeks for the 9800GX2, later for the 9800GTX. The cards will be 10.5 inches long. Who knows if they will be worth the price.
4) I would not expect a price drop because of high end announcements. The 8800GTX and ultra may drop.
5) I am not an expert on overclocking, but I think you are ok. A 2x2gb configuration would be better than 4x1gb.
6) I would suggest the evga 8800GTX-512-G92. It is a bit faster, and it has a very good cooler that expels the hot vga air out the back instead of recirculating it and heating up the cpu and vga card. With EVGA, you preserve the option to use their "step-up" program within 90 days in case the 9800xxx should appeal to you. EVGA also has good warranty and support.

It is not easy to program a multi threaded application. Game programmers have little incentive to do so, they want their games to run ok on the most common hardware, which is not the highest end. There are exceptions. Most games are vga limited. If you are doing lots of multitasking, or use apps which you know can use 4 cores, then a quad is good. Do get plenty of memory for multitasking.