My cousin [she's 16] and I saw it last night, and...umm...
We LOVED IT!!!
Phew. xD
I was so surprised, Disney definitely did go all out for it.
It made the first two look like crap.

The dancing and choreography was awesome, and songs were very catchy as usual. We were just going to laugh at it but ended up loving it. xD
I can't pick a favorite number, but I really loved the little houses in "Night to Remember". And "I Want It All" was crazy. And Zac and Vanessa doing the waltz in the rain was really cute. Oh yeah, and Corbin and Zac turning into little kids in "The Boys are Back" was adorable! All of it was actually really cool.
Wow I can't believe I actually admitted all that. xD
Nobody believes us that it was actually really good, haha.
But phhheeww, I feel so much better.