go, jib park was kind of empty this weekend, but they'll fill that right back up soon.
and for the jumps, there are a lot, and they are decent size, but if you are going there for jumps, don't go. they all have this weird style knuckle that rolls over, instead of having a solid lip like the ones everywhere else. and they are icy as fuck. and there are a ton of noobs everywhere. however this is the east coast, and thats to be expected.
My advice: hold off until feb break if this is the one trip you are going to make, or even march. when sunday river is warm, it goes off.