Is there an issue in OSX Mountain Lion or Safari, that it starts jumping out as you are writing a forums, or say FB?

I've been having a problem the last couple weeks, where as I am typing in comment sections in blogs, or on FB. Typing along and for no apparent reason, it skips out of the area and just moves to a random place on the page. I can take it back to where I was, and it has not been posted. This has happened a lot lately....has Safari gotten extremely sensitive with the new updates?...I have a MBP circa 2009. If there is anything I can do?