Whilst straight away I can see how that feature will save me a good few hours editing time on the average wedding I think it is worth keeping in mind the type of images used and what the results actually looked like.
On the girl on the bench example I wouldn't be happy with the shadow under the bench, and this is just seeing it at really low res. I can't help but think on the last example the selection was kept to break up the fact that the fill would still be visible when it was taken away.
In CS5 and LR3 I was really hoping to see a closer integration between the 2. Fancy new features are great, but what will really save me time is workflow streamlining and speeding up the overall program. I am yet to try beta 2 but the first beta only lasted one afternoon before it got binned. I want to be able to pass a Lightroom DNG over to CS5 apply some edits and save, and have the results display in LR but keep it as a DNG based on the RAW file that I could continue to edit in LR if I need to. I spend a lot of time outputting and inputting between LR and PS, having access to PS tools in LR would be even better!!!
PS is a professional tool, I wish they would put more focus on how professionals use their product rather than building layers of complex tools on top that no one really uses that much. The last wedding I shot was over 1,900 shots with over 400 presented to the client. Now that is a hell of a workflow based on the current system I can tell you!
Cheers
Cris.