I was in your position a couple of months ago. I was looking at the Canon 60d, 7d. Never really been a fan of Nikon, but not for any logical reasons. Just didn't associate myself with the brand (even though they take good pictures). I had been extensively researching for a couple months prior, but the Pentax never came up in my searches.
Something to consider when researching is that each camera has it's issues, and they always seem worse than they are on the Internet. More people seek out forums to post problems they have with their merchandise then the people who have no problems at all.
The D7000 and the Pentax K5 both utilize the same sensor, which is manufactured by Sony. Each camera's software, design and lenses dictate how the sensor performs in each body. However DXO rates the Pentax K5 as the best performing APS-C crop sensor camera on the market. It even out performs the Canon 5d MKII in some areas (dynamic range). 14 full stops of dynamic range at ISO 80.
As for lenses...Pentax also makes some of the highest quality prime lenses available. I should correct the previous member on here that stated every single lens will work that Pentax has made. That is not true. Every single Pentax K-mount lens ever made can be used. The other and older M42 screw mount can be used, but with an adapter. K mount lenses mount like any other lens made for the Pentax dSLR line. Most can be had cheap as well. Their new lenses (especially the Limited lenses) are very very good. There are some little details in Pentax lenses that make them particularly nice to use. The cheapest kit lens (18-55 non weather resistant) doesn't rotate when you focus (unlike the cheapest lenses from Canon, for example) making them more friendly to use with some types of polarizers and other filters. Pentax also makes Weather Resistant 18-135s and I believe some zooms and wide angles and primes. Most get great reviews. Paired the weather sealed body with a WR lens, and you don't have to run inside when it rains like most crop sensor bodies. Their macro lenses seem to be good as well.
The autofocus in my experience (and others) is that it is quick, snappy and accurate. If anything has been out of focus for me, it's been my fault. It does like light to be able to auto-focus though. But then, most do.
I honestly thought I was going to be a 7d owner earlier in the year. I was hesitant to pull the trigger because of the price for just the body, plus lenses. I randomly came across the Pentax K5 reviews, and literally could not find a bad review on it, or one where it wasn't recommended. Combine that with a sale price of under $1000 for the body and kit lens and I was sold. I realize this sounds an awful lot like paid review, but I'm just extremely happy with it. Solidly built, weather sealed, super quiet shutter, great lenses and controls. One dial at the front for shutter, one at the back for ISO, and hit one button and the rear dial turns to aperture. So easy and natural feeling to me.
Those are some of the reasons why I put my hard earned money into Pentax. I think at this price point you'd be happy with the d7000, 7d, 60d, or K5. Go out and handle them in the store to see which one feels comfortable in your hands. That's the best way to find out.
The entire first page of my flickr (with the exception of "blessed are those with a voice") are shot with my K5. Have a peek if you want some examples, and good luck with your purchase, what ever you end up getting!
Flickr: Gn!pGnop's Photostream