I have a feeling that if one is patient; that exact feature may show up in LR 3.x.
I think some of core features currently missing from Lightroom (i.e.; not "Stability, Speed, Image Quality", etc.) may be addressed in the newest release whenever it comes out, or in the subsequent .x releases.
Features I'm looking forward to seeing:
Distortion correction (along the lines of PTLENS)
Proper softproofing capability
Picture book layouts/capability
Other nice to have stuff:
True "plug-in" ability (ability to have plug-in's in the non-destructive pipeline)
Panaromic stiching capability
Can't wait to see how 3.0 turns out; the beta is pretty good!
Todd in Chicago
I kind of hoped for a tool/hack to somehow estimate correct values to enter to lightroom vignetting tool... so the news is bad