OnOne has just released a free "public preview" of Perfect Layers, allowing you do edit using layers in Lightroom. Very cool stuff, and especially for anyone running LR without PS CS, or anyone who can't decide whether to get LR or PS - makes the decision easier (imo).
Oh wow - thanks! :D layers in LR would be the most useful thing *ever*! Except perhaps toilet roll. That's pretty useful. LR layers come a close second though!
And have you heard? Toilet roll also now has layers!!