Personally, I love it.
I was getting tired of the Peter/MJ stuff, so its nice to have a nice break from it, so both characters can finally mature and grow up.
I also like it, because for the first time in a REALLY long time, Peter seems genually happy. I've never seen him this happy with MJ at all. I don't know, but it just seems like Kitty makes Peter less angsty and more pleasant to be around.
I also like it because we finally have a chance to have more X-Men/Spider-Man crossovers.
Given the popularity this pairing has generated, I wouldn't be surprised if this story is featured in ultimate x-men at some point down the road. I heard there are definately plans for it that are already in the making.
I hope they stay together for a little while, like for a year or so, before they eventually break up and ulitimately put Peter and MJ back together.