At this point, no. At a basic level, 64-bit computing allows for more data to be accessed at once, but software has to be written to take advantage of it. Since there's such a small install base to consider, software vendors don't consider it a priority. And truthfully, neither does Intel, else the first Core-duo processors would have been 64-bit rather than 32 bit.
There is a slight performance gain in some instances, but this is reall only shown in benchmarking, and isn't practically noticable to a regular user.