Other than the new Pauline and Paul characters, though I haven't really played with Paul, there's a lot of content. A bunch of it are included scripts and such, so they'll come in handy. As far as the objects and other Poser characters, no I've never been a fan of any of them, but you never know.
The new Construct, however, is an big upgrade from the old Ground plane I've always hated, though I've been playing with Bagginsbill's EnviroSphere instead, and like it. It's free, and SnarlyGribbly's got a new script that uses the EnviroSphere (with BB's permission). That I haven't played with yet, but want to.