I'd advise you to try and not compromise on your camera choice, and to, essentially, get the best equipment that your money can buy right now. If you've already had/used/enjoyed the Nikon D60 and you know you're into photography and likely to continue with your hobby, then try and make the investment in nice equipment.
If you're willing to forego live view for the k-m, there's no reason you shouldn't be looking into the K200D. It's a higher-level, more capable camera.
It's true that the K20D is an incredible deal right now, but it's also outshone by the K7. The K20D is a good camera, but the K7 has a faster AF system, improved live view, and a much faster continuous shooting rate, among other features. The K20D is also extremely hefty. You can likely find the K7 kit, possibly even a two-lens kit with some extras, on Ebay right now for ~$1200. The kit lens with the K7 is weather sealed, too, which will add to the ruggedness of your set-up.
Essentially, you have four choices:
Go with the K-M. A lower-end, entry-level camera without weather-proofing, tough build, or live view.
Choose the K200D. A slightly-higher-than-entry-level dslr, with weather-proofing and tough build, but without live view.
Choose the K20D. A mid-range dslr with tough build, weather-proofing, more advanced features/controls than the K200D, more mp than the K200D, and a rudimentary live view system. A good deal right now, but has a hefty body and a slow-ish AF system.
Invest in the K7, with a smaller body than the K20D, but with more advanced features and improved handling, AF, and live view, a weather-proofed body and kit lens, and a lot of room to grow.
Honestly, if I could do it over again, I would likely have invested more initially and gotten a more advanced camera. It's hard to tell when you start out whether or not you'll enjoy photography, but after only 7 months with my K200D I'm starting to feel the need for an upgrade.
In the end, the decision is yours. Good luck, and let us know how you get on. Espeically if you choose the K7. I'm dying to know what it's really like in practice.
Nikon D300 / 35mm f1.8 / 300mm f4 / TC-14E II
Pentax K200D / DA 18-55mm / DA 55-300mm