Early reviews seem to focus on the kinds of things that win the minor oscars (costume, sound, cinematorgraphy etc). And they are glowingly positive. Likewise the acting is good, even Han Solo (I read he doesn't just turn up for this one, unlike certain other franchises...). But some are suggesting the story is good on concept but that it doesn't deliver consistently.
Which pretty much reads like the original BladeRunner, so I'm guessing that if you like the original you'll like 2049. If you didn't, then the chances are this will leave you cold.
FWIW, I'm really looking forward to it and hope to see it on as large a screen as possible (IMax probably).