I was interested to see what the new MSN adCenter release had to offer. Generally it seems to be mostly a cosmetic upgrade... so far as I can tell, all the same pieces are in place, and if there's new functionality, I haven't uncovered it yet.
Is it better? Sure, I guess... the interface seems a little snappier, and (I think) is more attractive as well.
On the other hand, there's been some grumbling over at WebmasterWorld. We'll be following this with interest, and not a little resignation: like it or not, if you advertise on adCenter, this upgrade is here to stay.