I'm not a great JJ fan but he is pretty good at telling a movie story for the generation below the average age of those that remember the original star wars films from the cinema.
Like it or not Hollywood has moved on and so has the audience leaving us just as a 1 small segment of a much wider one. We probably aint the biggest movie going demographic anymore no matter how much we would like to think we are.
On balance the nerd in me was horrified by the bastardisation of the Star Trek back catalogue in his 2 versions - but taken as standalone and switching off the nerdy part of my brain leaves me actually reasonably satisfied with both. Star Trek improves with repeat watching, and I expect the sequel will too. God knows they are far superior to some of the dross in the series such as the Final Frontier, Insurrection and Nemisis springing to mind.
As to the TV list GreggS lists out above - that other Darling of the Nerds (counting myself among them) Joss Whedon - doesn't actually have that great a record - whats the point of appealing to the nerds with Firefly and Dollshouse if you can't appeal to the general public as well, and Im not even going to mention Agents of Shield (shudder). Whilst we're on that subject he's going to be lucky to have Age of Ultron hit the same mark as Assemble!
Movie sequels generally suck - for every Godfather part II or Aliens or T2 there is an Alien 3 or a Terminator Resurrection.
On balance I think we're being a little hard on a guy that has an almost impossible act to follow as he's not up against a Movie but a whole piece of culture and mythology and as long as they are mildly better than the second trilogy and contain no JarJar I'll be reasonably happy.