Nope, it not not better. Gravity currently 96/100 from just 9 reviews, and not a single new review added for the past couple of weeks. In Metacritic, Most anticipated movies get the most reviews. For an example, MOS and Elysium both got 47 reviews. So its the same for Gravity. When its all done with 40+ reviews, the metascore would in early 80s.
Ben Kenigsberg from AV club says, Watching Gravity often feels like watching an especially long prep reel for Star Tours, without ever being allowed to board the ride.