No they are not considered part of the same universe because Marvel actually does not own the movie rights for the X-Men (or Spiderman for that matter). So you will never see a crossover of Hulk vs Wolverine which would be a really cool film.
As to the Batman thing, I've said it before & I'll say it again. All of these modern day fans of Batman need to get down on their knees and thank God for a guy by the name of Frank Miller. He single handily remade Batman into the character he is today when he wrote the mini series Batman:The Dark Knight. The irony of that is that his Batman wasn't even set in the DC universe and was really more of a futuristic "what if" story.
But it certainly made Batman go from campy and fun to the dark brooding story's you see to this very day. I don't know if any one comic book series has ever impacted the entire comic book industry for a longer time than those books did. It was published in 1986 and almost 30 years later the tone and setting for that Gotham are still in effect today.