I vote that it doesn't really matter. The only difference is the clock speeds but they all more or less perform the same.
Yeah, I suppose you're right: http://www.videocardbenchmark.net/video_lookup.php?gpu=GeForce+9800+GTX%2F9800+GTX%2B
. Oh well, I guess I'll find out for certain once the system is built. Still, hope it turns out that it's the faster of the two cards. Plus, the GTX+, with its die shrink, consumes a little less power, runs a little less hot, has its stock clocks already set at higher frequencies, and overclocks A LOT better than its earlier 65nm counterpart. Keeping my fingers crossed.
Thanks for your help folks. Guess it's just going to have to be one of those "wait and see" situations.