Using JOIN is considered better for reasons of standardisation and readability, not performance. For a simple query like yours, you will see no difference in the query plans.
Using JOIN is the ANSI standard way of doing it. The old style outer join using *= has been deprecated in SQL2005, and you can only use OUTER JOIN syntax.
From the readability side of things, it makes it obvious which are the JOIN columns, as opposed to those that are genuine WHERE filters.