I liked 1 and 2...but I played them when they first came out, back when they were considered top tier, AAA, "this is why I bought a PS2" games. Couldn't get into 3 at all (too corny.) This seems like a big improvement on the previous 3, but I can't get into it right now.
I really should stop opening new action games immediately after a 2 hour session with Ninja Gaiden. I end up hating all of them (NG2 included

)