Although it didn't die yet, it certainly doesn't live up to its potential.
Then you could see tables of what you listened to most, see what your friends listened to, and get recommendations.
I think what happend is that last.fm failed to get deals with the recording companies, while Spotify succeeded (somehow?).
Nowadays I use Spotify like everyone else, but I feel like last.fm gave me much better recommendations. Probably because it had many many years or listening history.