I'm sure Capture One would beg to differ as they claim superior image processing results.
Also quoting StephaneB: I think Adobe's problem is that they have by and large solved the question of processing pictures.
I have no doubt that there are other RAW processors that might do a better job than Lightroom. I can certainly believe that there are other applications that can do a better job at correcting lens aberrations, adaptively sharpen, drive a printer with amazing accuracy, and make a good cup of coffee.
But...
Lightroom, ignoring some of the recent "improvements," easily does it all from ingest to cataloging to processing to printing. It's a single package with a reasonably consistent UI. And it's "good enough." That's Lightroom's primary advantage: it does all that I need it to do and does it sufficiently well for my needs.
I understand that some photographers demand far more from their workflow than what Lightroom can offer. Heck, even I have a copy of DxO that I fire up on rare occasions. I might even dip into a plug-in or two--I might even use PS6 for certain things--but for the majority of what I need to do, Lightroom just works.
Notwithstanding the huge number of posts in this forum dealing with deconvolution sharpening, custom DNG profiles, and other such technical discussions, I'm willing to bet that the majority of photographers using Lightroom, enthusiasts and pros alike, would agree with me that it is "good enough."
I know there are competitors looking to get a slice of the pie. Capture One, for example, has made considerable changes. Even On1's recent release has added features to make it a more well-rounded solution. For me, though, the additions and changes have not been a compelling reason to invest the time to convert. Capture One, for example, seems to have their manual delivered mostly as videos. In my case this is a terrible way to instruct. On1's stuff doesn't really have a database backend...or at least not one that's as well integrated as Lightroom's solution.
At this time, there are only two reasons I'd seriously consider moving from Lightroom: the discontinuance of the perpetual license or Adobe so changing the UI to something else--the latest Import changes being an example--that I can neither tolerate nor easily adapt to.
The only reasons I can see upgrading to the next version of Lightroom would be additional camera support that I HAVE to have (grin), a threat that I could never upgrade again, or the addition of some really slick feature. The last would include far improved processing (remember, though, the current is "good enough" for me), improvement of the current functionality--such as making the book module much more flexible, or adding some new compelling feature that I can't live without.
I don't know that the processing pipeline is going to be improved much, apparently Adobe has decided improving the book, web, and slide show modules isn't a high priority, and for the life of me I can't figure out what else I'd need. Because of these reasons, the only way I'll update is to keep a current, perpetually licensed version on my hard drive to ensure that I can get the next current, perpetually licensed version when it comes out.
This isn't a very good answer to the question "Where should Lightroom go next?" But it is a personal agreement with the statement, "I think Adobe's problem is that they have by and large solved the question of processing pictures."