Looking over the year, it looks like most of the shows I was interested in survived the entire year. The exceptions to those were Threshold, and Reunion. The latter of which I was pretty sure was going to be canned, and honestly wasn't great, so no huge loss, although it would've been nice to give us the story. Threshold, though, was a very good show, with some smart writing that was very fun, and had an arc in the background that was quite interesting.
Supernatural, Prison Break, Bones, and to a lesser extent (Much lesser), The Unit have all been very entertaining, if not outright good shows, and I'm glad I started watching them, and am very pleased to see that they were given a chance, the audiences found them and embraced them to the extent that they'll be back next year. Once in awhile, the system works. =)
And on that note, my usual shows, 24, Lost, House, Medium, et al, are all coming back for more, which is great, since these shows have just gotten better this year, overall. Lost had a slow start, but the second half of the season was mostly great. Still upset about Shannon, though. *shakes fist*. 24 continues to be a great action popcorn show, and has done nothing but improved over the last few years, in my opinion, almost as good as the first year. At least we've had no 'amnesia' silliness, and no cougars.
Also, came a little late to the table for Veronica Mars and BSG, which I'm watching on DVDs, but much of the above also applies, since for me they are 'new' shows, AND it's good to see them still moving forward on the schedules.
Overall, I'd have to give this past season a B+, maybe an A-. Lots of great hours of television, with a few missteps, and they didn't stomp all over my shows and can everything I was enjoying a few weeks into it.
A nice change of pace after being dicked around the last few years.