PCI-E 2.0, a necessity?

Okay, first off happy new year, hope you have a good one.
Anyway, here are the specs of my pc relative to this question (have not received yet but ordered):
EVGA GeForce 9800 GT Dual Slot 512MB DDR3 PCI-Express 2.0 Graphics Card

XFX nForce 680i LT SLI Motherboard - OEM, NVIDIA nForce 680i LT SLI, Socket 775, ATX, Audio, PCI Express, SLI Ready, Gigabit LAN, S/PDIF, USB 2.0

Okay, so first of all, I noticed that this card is PCI-E 2.0 while the mobo i am getting only supports PCI-e x16. Now, I am quite sure that PCI-E x16 is not a bottleneck for the 9800 gt as I am quite sure that the speeds are not nearly close to the bandwidth of PCI-E x16. So it shouldn't affect gaming performance, right?

Also, while we're on this, for people with experience with this mobo and gpu, what overclocks are you getting?

Thanks very much in advance!

Thank you very much for the answer. Much appreciated. Ok, I'm not going to be going in to muti-gpu for a while, hence as you said, there isn't a real need for it so i guess that clears it up. Thanks!

Also, as for anyone who can help me with the clock speeds, it would also be a big help.