I would say he kept it in the mainstream. If Nu Trek wasn't a success, it would have been strike 3, and the studios might have given up on the franchise.
Abrams is on the record as saying he was never a fan of Trek. That would be all the more reason to study a bible, if just to avoid some crazy changes to a character.
Nu Trek is obviously a blockbuster movie--big explosions, nonstop actions etc. the somewhat silly gimmicks like the Spock and Uhura relationship, (my opinion) but it works--it's making money.
I still have a hard time with the Kirk going from cadet to captain in a few short minutes, and the Spok/Uhura thing, but the movie did put Trek back in the spotlight.
The thing is, if it keeps following the blockbuster formula, then the danger is that withing a few years there will be a reboot yet again--like Spiderman, Superman, Batman, ect.