in my opinion soundcloud is one of the hottest most amazing startups out there. they reached a critical mass of important artists already a while ago. the fact that they're located in the epicenter of electronic music is just the icing on the cake.
recently i had a complete harddrive failure and lost 500gig of music. since i couldn't access my backup for 2 months i was limited to streaming music. after a short while i realized that i needed nothing else than soundcloud to completely satisfy my daily need for good music.
the update seems to bring soundcloud closer to twitter's model of 'social'. i think this is a perfect fit for the site. i sorely miss an equivalent to twitter's lists feature, however. further more i'd like to create playlists in the browser and not just in the macstore app.
/edit: about the 'list' feature i mentioned: it'd be awesome to create lists of artists within which i'd be able to switch between recently liked tracks of these artists (with full waveform-player display) and recently self-released tracks.