OK, now we've gotten more specific, the C/N/P folks can get back to disagreeing with each other.
It sounds like you're thinking of the K100D, not the K10D (which just came out a week or two ago.) Featurewise, the K10D beats every other DSLR priced anywhere close in most every category, hands down, and is 10 mp like the XTi and D80 (in fact, it's the same sensor as the D80 and Sony.) It's an astonishing camera for being under $1k. It's so new that there are no "pro" reviews yet but you'll find a few people with them on the Pentax forums at Steve's Digicams and DPReview. There is a preview at DPReview that's worth looking at.
As it's brand new, it's selling for close to retail - $900 for body or $1,000 with lens - versus $513 after rebate for the K100D. The question being asked on the Pentax forums is if it's worth nearly double the cost - in other words, the K100D is plenty of camera for most people, but the K10D does improve upon and offer the few features that the K100D lacks. The same question can be asked with the Nikons, if the D80 is worth the extra cost over the D50. For many, it's not. You get into diminishing returns for your money when you start looking at the $900+ price point, IMHO. I would very seriously consider starting with a K100D or D50 and later upgrading if you decide that you need more camera - they have most features you could ask for, can nearly match the image quality of their big brothers, still put out a huge photo (look at a 6mp pic at 100% on your monitor - it's enormous), and give you a LOT of leftover money for a few more lenses. Your existing lenses will work with the higher models, also.
As like the article that Jann1033 linked to says - do not fall into the trap of assuming that more megapixels are automatically better! This is especially true in the PnS world where the more mp, the more noise and consequently the worse quality you'll get - with DSLRs, it's not quite as bad, but realistically, there isn't a tremendous difference going from, say, 6mp to 10mp (and very little between 6 and 8 or 8 and 10.) Megapixel count should be one of the least important factors when choosing a DSLR.
Anyway, you sould consider the Sony Alpha, too, if you are sold on spending more money on the body. Both the Sony and the Pentax feature in-body IS, which is a huge advantage. Canon and Nikon require you to buy expensive (sometimes VERY expensive) lenses to get IS, and forget it on something like shorter prime or shorter zoom.. meanwhile, the Sony and Pentax stabilize everything. The K10D even stabilizes rotationally. The Sony, Pentax, and (I think) Canon also have sensor dust cleaning systems. Still, If I was tied down and forced to choose between the Canon and the Nikon, I'd have to go for the D80 over the XTi - I don't care the some of the design decisions and don't like the ergonomics of the Canon, and it seems more like a cut-down model than it should for the cost.
As for autofocus points, if I'm reading the specs correctly, the Nikon D80 and Pentax K10D have 11-point systems, the Sony Alpha and Canon XTi have nine-point systems.
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So, when I get back, I'll post some pictures.
