We recently replaced the air conditioner's compressor and with the new code it looked like the car was going to quickly become expensive to maintain. The engine and the transmission both were fine, but the other stuff can quickly get expensive.
The Fit was a really good car, it was very reliable for over 5 years. The maintenance didn't kill us off either. We had compared getting a new one compared to buying the Prius and were having trouble making up our minds, the reason we had originally decided to hang onto the old Fit for another few months.
Tony - the funny thing is that I really don't have any particular desire to add more lenses. There are several I'd like to buy some day, but don't feel deprived because I don't have them. And I'm very, very happy with the K5, so I'm not reading threads about speculating what it's replacement will be like (other than I was curious about the new 24 mp sensor, to see how it was as far as noise and dynamic range). There's really not any new features around that I'd be interested in, and I don't feel that the K5 is limiting me (I feel like I'm the limiting factor - I still don't know how to get the most out of the K5). So buying the new car isn't going to frustrate me photographically at all.