I bought my 07 Fusion w/ 30k on it last year, and it is a great, all-around commuting car. It doesn't have the acceleration and power that I prefer, but it more than makes up for this as far as ride quality is concerned. It is one of the SMOOTHEST riding cars you'll ever have. I literally keep falling asleep while driving due to the low wide noise and smooth ride. The interior is very nice and neat, and of course the exterior meets a tame middleground between sophistication and sportiness. The seats aren't the comfiest, but they're good. So, if you have kids and a tight budget, and you're not a speedster, this is a great car. It's reliable and doesn't feel cheap.
-Ride quality. -Reliability.
All improvements I would suggest have been made in the new 2010 Fusion. I'm excited to test drive one in the future!