I can't see it being anything but fabulous. Last March - my DH and I visited (we stayed at the Omni) and we went pass the JW Marriott in Cancun. We wanted to take a look around but the Marriott was still closed (even 4 months after that bad Hurricane). Anyway, the Marriott opened this past Fall - and received a FULL make over (as did almost all the hotels in Cancun). I have every intention on staying there next Spring (March 08) so I'd love to hear your review once you return. Also, cancuncare.com has some wonderful people posting great things on their message boards. Also, according to Tripadvisors.com, Marriott JW is #3 - and that’s pretty good considering that there are many 5+ star hotels. The Marriott JW is a Five Star. The Omni was a Six Star hotel, and I think that Marriott is nicer.
BTW, my DD (pictured below) - is waving from that Omni Cancun room - it has been completely rehabbed since this picture was taken. The hotel had only been open 1 week prior to our check in (after the hurricane) so we didn't get the rehabbed rooms.