Looking at some comments and emails, I think it might be worth mentioning that the past 35 or so pictures posted here were all made with a Pentax K5 during my intensive* two-week opportunity to experiment with a borrowed camera. I got a lot of pictures I like while working with it, and will be posting quite a few more in the next week or so. I like some of them enough that I'll eventually select them for printing.
My decision not to buy one is because, first, for the pictures I'm currently interested in making with digital capture equipment, I find the Lumix GF1, a very different type of camera, a better fit than a dSLR. Second, the optical quality I get from files from the Lumix short prime lenses delivers better prints at around 20-inches wide than files from Pentax short prime lenses for their digital cameras. I do nearly all my work with short lenses, and I detest zooms. As an aside, the Pentax 12-24mm zoom delivers astonishingly good performance at f/5.6 or f/8, despite not being classified as one of their premier, or Limited, lenses. But I just can't stand to use zoom lenses.
I'll continue to use my K20D where a dslr has advantages (the GF1 Electronic View Finder—EVF—can be difficult to use in full sunlight, for example) but the $1400 cost of a K5 just can't be justified for the use I'd make of it. I need the money for gas. So, just to be clear, my decision to pass should in no way be taken as a "don't buy" recommendation. On the contrary, if you are working with a K10/20 (I've never used a K7) and can afford to upgrade, you'll love the K5.
If you are interested in this techy-doo, you might want to scroll back to Saturday's post and click on the comments, which have continued into this evening.
* I seem to have shot 2,183 captures, probably a third of them boring objective testing of SBR and AF calibration, the rest actual attempts to make real pictures. I hope that doesn't strike the lender as a variation on borrowing someone's car for the weekend and driving it to Vegas...