I think that the reaction to ST'09 will depend on the continued success of the franchise, and what direction it moves in. If ST'09 is the springboard for a healthy, successful run of feature films starring this new cast, and set in this new timeline, then the movie will probably hold up well and will be highly regarded. If the next film fails, and the franchise falls apart again, then ST'09 will likely just be a small blip on people's radar. Trek fans will remain torn - some will still love it while others will proclaim in the Abramsverse as an "epic fail" (basically the way things already are).