Now the advice
Go and pay a visit to your local dSLR dealer and test two very important things that would make the difference between a camera you're going to use and enjoy and a camera you're going to be uncomfortable with.
While it's kind of important to a point, I have found that I can pretty much get use to any camera and layout, admittedly the digitals are a lot more complex than film cameras of the past. The biggest concerns IMHO are weight, will you be bothered to lug it along, battery life and the ability to use what's locally available should electricity be N/A, water/dust/condensation should be a consideration especially in an all electric camera. If you consider yourself a serious photographer a drop of rain or the potential for it should not be a consideration on if the camera comes along.
I ride motorcycles sometimes in the rain and sometimes out in the middle of nowhere China, I had a point and shoot and the battery went bad........no more pictures till I could find another exotic battery and convert the camera to accept a AA battery pack.....so the ability to use AA's should not be underestimated if you do a bit of traveling.
If the D-90 had the weather sealing and the ability to accept AA's either in body or in the supplemental battery pack I'd probably have gotten one of those or countless others I have held.........like the Olympus E620, great size and weight but not weathersealed even though it looks like you are looking down a tunnel to take a picture, the Sony a700 has a great viewfinder compared to the Olympus but is pretty heavy, the better Canon bodies and lenses are huge (compared to in body stabilized lenses) and again are not sealed.............I can learn to adapt, to the camera, layout, whatever, but the camera is not going to adapt to the weather
.......and the heavier and bulkier it is the less lightly it is to come along for the ride anyway.
I find the Pentax line ticks the most must have features I feel are valuable for the types of conditions and environments I might find myself in. If the K-7 hadn't have come along I'd probably be using a K200d or 20d........or even a K10d with a weather sealed lens. As it is I'll probably wait till the K-7 is readily available.
................it's not always about how it feels in the hand, for me it'll depend more on what, where and how I will or won't use it.