Most of 2008 has been like this for me too. I barely rode at all until the TdF was on TV; that got me sort of motivated, but not much. I've done more swimming (lake and ocean), and much more walking and hiking on days when I'd normally be riding.

SouthernBelle has a good point, and it's something I started doing a couple of months ago: I ride for pleasure now, not for sheer mileage like I was doing. It was becoming sooooo boring! When I ride now, I'm looking for a new road to explore, a trail I've never noticed before. I ride slower and actually see sights I never botherd to look at before. I stop more often, just because. I take my GPS and do a little caching.
I'm enjoying my rides much more than I have the last couple of years.