Some HDTVs do a much better job upscaling standard def pictures than others. Don't know which model(s) you were looking at, but my Panasonic 50" plasma does a pretty darn good job with a good standard def signal to the point that I don't mind watching it at all (sometimes I even have to doublecheck the channel to see if that I'm not on an HD channel). That said, there are some substandard broadcasts that will never look good on any HDTV, but those are in the minority and most are very watchable (this will obviously vary by area/provider). I've seen standard broadcasts in the stores too, and they always look much worse than they do in my home. I tend to think they have a poor signal spread among too many TVs, and the HDTVs themselves are almost universally poorly set up, which only makes the situation worse. Even the HD broadcasts don't look that great in the stores, which is probably why you often see them using blu ray to demo HD.
Anyway, most of the stuff I watch is available in HD and that content is and will only continue to expand. Everybody's different, but in my experience I end up seeing a stunning HD picture the majority of the time, which far, far outweighs those times when I have to watch a standard broadcast. I think you'd be throwing the baby out with the bathwater if you're using that as an excuse to not buy an HDTV, and there are some scorching deals to be had now since stores/manufacturers are desperate for sales. For what it's worth...
Anyway, most of the stuff I watch is available in HD and that content is and will only continue to expand. Everybody's different, but in my experience I end up seeing a stunning HD picture the majority of the time, which far, far outweighs those times when I have to watch a standard broadcast. I think you'd be throwing the baby out with the bathwater if you're using that as an excuse to not buy an HDTV, and there are some scorching deals to be had now since stores/manufacturers are desperate for sales. For what it's worth...