This thread interested me enough to try out DPP with my 30D and Rebel files. The user interface isn't half-bad, and it's true that it is much better with default white balance. I also found the automatic chromatic aberration/ purple fringing reduction pretty effective. However, white balance can easily be adjusted with LR, as well as chromatic aberration/purple fringing reduction.
I also found that chroma noise reduction was not as effective as LR with my high ISO files... it appears more conservative than LR even at higher settings (which some might like, but I find it lacking).
However, I find the basic sharpening lackluster. It is simply not versatile enough to handle capture sharpening the way that LR 1.4.1 can. DPP's sharpening reminds me of LR 1.0's sharpening, albeit with even less precision.
Exposure wise, there was no highlight recovery function that I could find. There is the possibility of achieving somewhat similar results with its curves function, but I find it far too fiddly when comparing it to LR's HR and parametric exposure sliders.
It is also interesting that Canon's own DPP raw converter is specialized for CRW and CR2s, yet it refuses to even display my Canon G9 CR2 files. It is understandable if Canon intends for DPP to be used with their DSLRs, but I don't see why they wouldn't include the G9 at the very least, considering that many people who have DSLRs may also have a compact they carry around. And, it is the same proprietary RAW format! LR handles all my RAW files, from every single Canon compact (and DSLR) that I've owned.
All things considered, DPP has very limited capabilities when compared with lightroom... simply on the RAW development level, all other workflow bells and whistles aside.