As a fan of both franchises, this author has some observations on the reactions across social media.
The reactions from the fans are what was expected, honestly. Of course, the normal split between people who love the idea of JJ Abrams directing Star Wars, and those that hate it. But, within each group are the interesting subcultures each fandom have grown up within each fan base.
Love It
Those who love the idea are split into three groups, with little overlap. First are the fans who loved the Star Trek reboot movie, and want to see JJ Abrams touch on Star Wars. Primarily, in this category, are fans newer to Star Trek but older fans of Star Wars. Since they are primarily Star Wars focused, they want to see what Abrams can do with their franchise, believing he 'updated' or 'improved' Star Trek to a likeable level.
The second group are also Star Wars fans, primarily. However, they hated the three prequel movies. They have been the ones clamoring for a new director for the series, though they've stated before they want George Lucas invovled in some way, creatively or overseer of some sort. The 'I hate Jar Jar' crowd is in this grouping, hoping JJ Abrams is more serious as to his plot, like he was in Star Trek and the soon to be released Star Trek Into Darkness.
However, the third group are Star Trek classic fans. These are the people who absolutely despise the new movie, and this is not just a small fringe minority of folks. At conventions like Star Trek Las Vegas, I know plenty of these people and some are my closest Twitter buddies. These folks are the ones waving, telling JJ to don't let the door hit him on the way out. They want their Star Trek back, the series, the intrigue, the ongoing story and drama that cannot be portrayed in 120 minutes on a 3-D screen while blinded with flares.
Hate It
The first group of these are the newer Star Trek fans, primarily, once again. They enjoyed what JJ Abrams did with the Star Trek movie, and want him to continue. Or even, much to the chagrin to the third group above, bring his vision to the small screen. This dashes those hopes, as JJ Abrams will not have time to do a television show, live or animated, on Star Trek while he is working on Star Wars.
Not surprisingly, the second group is like the third group above, Star Wars fans who do not want to have their beloved franchise turned into a slow, plodding episode of Star Trek in their minds. They dislike any notion of someone from the Star Trek televsion shows ever appearing even in a minor role in their movies, though I believe more than a few did. Both drew actors from the same pool in the United Kingdom, so some overlap is inevitable. Just like it is with another television franchise, Doctor Who.
Conclusions
What do you think? Do you like the idea of JJ Abrams directing Star Wars? Which series do you like, or do you like both? I admit, I'm pretty much in favor of this move by Disney, assuming the wave of rumors is officially true. JJ Abrams did make Star Trek very much like Star Wars, and I honestly think he is a better fit for the Star Wars franchise than he is for the more sedate, cerebral Star Trek.