Just caught this. I wasn't sold on Halle in the trailers but she definitely owns the role, especially after she turns human. OTOH the other mermaids were all pretty terrible, especially in the cheesy final scene. Overall definitely worse than Aladdin, about on par with BatB. The new songs were all embarrassingly bad, I'm actually shocked LMM did these since I usually like his Disney songs.
Princess Live Action Rankings:
A: Cinderella - improves on the original in every way
A-: Aladdin - mostly good and lots of fun, Speechless is the only good new songs in these remakes, however Jafar was a big stepdown from the animated version
B: BatB/TLM - much worse than the original, especially the new songs, but not terrible on its own
F: Mulan - dishonor on you, dishonor on your cow!