Err the Roman Emperor? I missed that part.
In Star Trek 4 the timeline could have changed, but the change would have occured after they travelled back in time. in the new movie the Romulan minning man Nero has been around for 25 years screwing up time, so ofcoures that's going to change things.
And we don't need a Hadron collector to tell us that each choice creates a new parallel univerese in Star Trek, because of the TNG episode Parallels where space was almost filled up with Enterprises (I wonder which one came from the JJverse?).
We were discussing today why the Enterpise engine room had so much unesscesary pipes going nowhere, in the end we came to the conclusion Starfleets Scotish engineers were payed for each meter of tube they layed down, hence the odd configuration.
Overall a fun film, the report below nails it spot on.
http://www.youtube.com/watch?v=02LgdXVkXgM