Nikon D90, Pentax K-r, or Pentax K-x?

I'm looking for a new camera (an upgrade from a Panasonic DMC FZ18) and I've narrowed my search down, or at least so I think, to the Nikon D90, the Pentax K-r, and the Pentax K-x. I'm pretty competent with a camera so the more "advanced" idea of the Nikon is a little more appealing. But what does that really mean anyway? All I know is that I want an upgrade from the camera I already have, not just the same camera with interchangeable lenses. Price is also definitely a factor though and the Pentax cameras are certainly cheaper than the Nikon. What I'm having problems with is actually knowing the difference between these cameras. It would be nice if someone could please help me understand the differences and tell me which one they think I should buy and why, assuming that they all are affordable.

They are all basically the same, dSLRs. Nikon is better for more technically oriented photographers. They churn out the most number of dSLR models with each bearing the latest advancements in digital photography. This is the reason Nikon is heavily favored by many professionals. The specs of their cameras are enough to make a room full of Nikonians actively conversing the whole night long.

Pentax is more suited for photographers who don't care about cutting-edge technology. It is a brand well recognized by the most experienced photographers. Recognition however can either be positive or negative. This is due to the fact that even if Pentax is lagging behind their competitors in technology, their users somehow manage to snap magazine cover quality shots with ease. You won't find Pentaxians huddled together bragging about their equipment. Most of them have at least one manual film lens in their bag that they try to hide when among Nikonians and Canonites. Pentaxians only love to shoot, use their cameras, and find means and ways to duplicate if not make better shots than those using better equipment.

Don't get me wrong. My youngest son uses a Nikon D50. I have a Pentax K-x. I maintain both cameras. I like the silent shutter mechanism of the D50 but I wouldn't trade the loud mirror slapping K-x for it. The D50 has most functions readily available at the press of a button while the K-x has them buried in menus. Still, I remain a Pentaxian for one unparalleled feature since the old glory days of film. That's the brightest viewfinder in the whole wide world of photography.