Really does seem to have divided opinion. I noticed on IMDB it's rating has slumped to a 6.0 (at time of writing). When it first came out it had a 7.8 rating. I think as more people have watched and reviewed it the rating seems to have levelled out.
Certainly judging by this thread it seems to have gotten a mixed reaction.
As for sequels, well, they don't usually depend on whether or not the first movie was any good. It depends on if the first movie made a lot of money. And the Karate Kid 2010 has made a reported $225 millon so far, and it hasn't even opened in some territories yet.
Bringing in that kind of dough on a reported $40 million dollar budget means that sequels are more likely to happen than not.
"Let your food be your medicine, and your medicine be your food"