I still use it all the time. I
it.
I'm not entirely sure how the front page works, but it seems like it only shows pins from a certain time period - like maybe the last 24 hours at most? I find it annoying because there's no place to view all the pins from the people you follow which seems to kind of defeat the purpose of following people. I do the majority of my pinning from the Most Discussed & Everything categories and subcategories instead since there is way more eye candy shown at once there.
I really hope the site isn't dying. I love love love the concept (way more than I love Facebook or Twitter) but the site is definitely experiencing growing pains and I think that turns some people off. But I'm still hoping that they'll be able to work it all out.
ETA: One other thing I was going to say is the number of pins that are shown seems to vary depending on whether the site loads properly or not. Like I might not see that many pins on the front page but if I wait a little bit (like even 5 minutes) and refresh, it'll add a bunch more pins that are older than the ones I already saw? I notice this happens on pretty much every page of the site so I think it's all tied into the server issues they seem to have a lot.