I think Adobe has to stop worrying about whether they'll cannibalize Photoshop with Lightroom, which I think may have crossed their minds... 8-)
If they plan to issue new versions of Photoshop forever, then it's going to inevitably become a more and more intricate photo-art program in which photos are only pieces of the whole. Straight photographers, who are working in a whole different aesthetic, don't need all that, but they do need the most ramped-up ACR in the world, and that might include some camera-specific plug-ins. I think some Adobe-ers see that now, and that the whole company will eventually catch on; if they don't, Steve Jobs might shove Aperture up their...er, aperture. Adobe has the resources. If there is clear, continuing demand for a Lightroom type product, I think it will get better and better, and so will the ACR function.
Photographers -- maybe amateurs and art photogaphers more than high-volume pros -- need a "darkroom" progam that provides cataloging and review functions along with complete adjustments for "straight' photography. Sooner or later, most straight photogaphers will go for one program, because it will become a standard like Photoshop. It's probably going to be Lightroom or Aperture; I hope it's Lightroom because I've been working with it, but I'm willing to move if Lightroom falters and Aperture comes up with a really great RAW facility.
Here's an idea for another Lightroom function: how about some kind of "exchange" feature, which allows Lightroom users to trade photos almost like cell-phone users do, but at a much higher and more sophisticated level? But still, **instantly,** so people can talk on-line about instantly shared photos, make suggested improvements, etc? You can send the check directly to me...