I have been using Flickr for a number of months now. So far so good. I like the feature set and I like being able to send friends of mine there to see images I have taken.
I think equally as important as the ability to upload and store tons of photos (I have a pro account) is the community structure. I have learned quite a bit just from joining up and reading the postings in several groups. Overall, it is a very nice learning experience as well as a great place to show of some shots of yours that you like.
Just as a point of personal preference, I don't just upload every image i take onto Flickr. I have friends that do that, and while they like that feature, it would drive me out of my mind if I loaded all my images up there. I have iPhoto and Lightroom for that. I use Flickr for the few that I really like, or want to share.
To be fair, though, some individuals really do have 100s of great photos on there.