I don't know, the earlier seasons could really benefit from the HD transfers since they were shot on film and drawn on cels. If you've caught any of the classic re-airings on FX (despite being cropped) you can really see the difference in quality and grain in the ink and paint. Personally I'm a huge fan of that stuff. On top of that, the HD releases of the earlier seasons could rid us of some of the horrible compression and interlacing that plagues a lot of the releases:
I'll admit, when I caught the Beer Baron episode, it did look pretty striking in many moments (you could even see paint outside the lines in some scenes)...but in others, it looked as if they couldn't locate the negatives in their entirety, and decided to upscale certain shots, as they looked smeary as hell (in particular, the scene where Homer was caught on fire, just before he decided to quit brewing and bootlegging), while other moments, where it seemed like the composition wouldn't work when cropped, they would just stretch the image (just look at the final shot of the episode when Homer makes the "to alcohol" line and you'll see). Thankfully, it was the only HD episode that aired on my channel that I've caught thus far.
Getting back to the whole DVD thing, yeah, it's a total screwjob to collectors and even worse to those outside the US (me included) as that would mean there's no official or legal means to view the series outside of television. I mean, I would kill for an entire series BD release (provided that the episodes are uncropped and all pre-digital negatives have been located), which is something that you cannot get in piracy with all the compression and such.
And while we're on the topic, how are the digitally animated episodes in HD? The two experimental episodes (Radioactive Man and Tennis the Menace) and the ones from series 14 onwards, how do they look?