Lets start with the Plot Summary and the Casting.
The first thing to remember is nothing is confirmed by anyone. Abrams has been consistent in saying it is a secret, but he along with StarTrek.com have made a number of ‘indications’. That being said, whoever has been submitting at IMDB went way too far…here it is with my corrections:

Plot Summary
According to a report filed on a reputable website, Matt Damon is slated to play the role of Cadet James T. Kirk. The newest installment of the Star Trek franchise will be an Original Series Prequel, focusing on Kirk, Spock, and McCoy during their Starfleet Academy days.
Reliable reports indicate: a prequel to the Original Series Star Trek (1966) probably including the characters of Kirk and Spock.

Cast
Matt Damon….Captain James T. Kirk (rumored)

Here is what was wrong and why it was changed:
1. Damon is not confirmed by anyone
2. how can he be both ‘cadet kirk’ and ‘captain kirk’ (especially as a 35 year old)
3. Academy plotline has been denied by Abrams
4. Mc Coy has never been even rumored to be involved
(really should have left it all blank to be hyper vigilent)

And the crew listings are riddled with errors as well
Here are the corrections noted in red

Director
J.J. Abrams (option) [Abrams has yet to commit]

Writing credits
Alex Kurtzman …screenplay
Roberto Orci …screenplay
J.J. Abrams …screenplay [Abrams is confirmed as writer]
Gene Roddenberry …characters
[NOTE:writers say they will use old characters so Rodenberry entry is OK]

Produced by
J.J. Abrams …. executive producer
Damon Lindelof …. executive producer
Bryan Burk …. executive producer
Alex Kurtzman …. executive producer
Roberto Orci …. executive producer

Original Music by
Michael Giacchino [Regular Abrams colaborator, but only speculation as of now]
[update: Giacchino has now confirmed his involvement]

Special Effects
Industrial Light & Magic (ILM) [have worked on Trek films before but as of now just speculation]

Budget
$100,000,000 (estimated) [$100M is a good guess, but pure conjecture]

[update: since the publication of this report IMDB has made some of the above corrections, they have changed the Damon listing to rumored and removed the plot summary…they other errors are still there]