On 2008, my views are roughly as follows:
1. I don't know that the GOP will lose the Presidency. I think we're at risk of it, certainly. But, depending on who our nominee is, and how the next few months shake out, we may be able to hold it.
2. I think it is likely that we are going to lose a couple of Senate seats at least. The GOP Senators I see as being at significant risk are John Sununu (hugely unfairly because if he loses, it will be punishment for Bush Republicanism, of which Sununu is about as representative as is Dianne Feinstein) and Norm Coleman (it is frightening to suggest that Al Franken might be capable of beating Coleman, but he's exceptionally good at raising money and has a platform-- and has anti-Republican sentiment swinging in his favor, even if he is quite mad). I also do not think there is much chance of Bob Schaffer holding Wayne Allard's seat when running against Mark Udall, given the way Colorado has been trending over the past five years (watch the map, it's been getting steadily more blue, to the point I don't think it's accurate to call it a red state anymore-- and Schaffer isn't exactly a moderate, the kind of Republican who maybe could survive such circumstances). Depending on whether or not John Warner runs for re-election here in Virginia, we may or may not have a decent chance of holding the seat. The advantage is, if John Warner runs, Mark Warner may not. But if John Warner doesn't run, Mark Warner probably will-- and then it's probably down to a fight between him and Tom Davis which I think either could win, but which will be very close.
3. In the House, I can see Republicans winning back and/or picking up a few seats (these might include CA-11, NY-20, FL-16, GA-8, KS-2, PA-10, TX-22, IN-9, OH-18, NH-1, PA-4 and maybe even one of the lost CT seats). However, that still doesn't get us to a majority, and the GOP will still have to worry about holding seats like NM-1, WA-8, OH-15, IL-10 , PA-6, NV-3 and CO-4 (the latter of which, I'll be blunt, is like last year's PA-Sen race-- I won't cry much if that goes; that's very much unlike WA-8, OH-15 and IL-10).
That's how I see this playing out.