I'm pretty sure Clarksfield has a higher TDP than any MBP processor in recent memory, though. So yes on iMac, no on MBP. We'll probably see a Nehalem MBP early next year, after Arrandale starts shipping in Q4.
I think we'll see an iMac/Mac Pro/possible Pro Apps event in late September or October, after an iPod event on or around September 8.