@PhilX,
This idea is similar to Heraclitus' 'you cannot step into the same river twice' argument, and would seem relevant to you as a physical human being - apparently in 7 years time a human body will have completely replaced all of its cells.
But I personally am inclined to disagree with this - it SEEMS to make sense to take all the variations of PhilX, physically and mentally, and describe them in terms of their resemblance to a kind of 'over-PhilX' - a Plato-like Form of the PhilX. Though the Form/Idea of you would not be exactly the same as you now for example, every variation of you that would ever be would have some resemblance of you.
Not that I'm suggesting Plato's WoF actually exists, but I'm trying to think along similar lines;)
Phil (www.philosophersblogofideas.blog.com)