As far as waiting for PCI-E 2.0, same answer as it was when people asked if AGP would be worth the wait: it depends. Note that it will be a long wait.
If the card doesn't fit THAT case, nVidia is in a lot of trouble...cuz it would mean their card won't fit in any case.
The mobo is a good choice, but if going SLI, the southbridge heatseak may block proper seating of the second card...dunno.