Hi all!
Found this thread while searching for posts that describe problems of using SQL 2008 x64 and Excel.
Here is an article I've written that talks problems and provides solutions for making SSIS work with the 64-bit Excel (ACE) provider.
http://hrvoje.piasevoli.com/2010/09/01/importing-data-from-64-bit-excel-in-ssis/
Kind regards,
Hrvoje Piasevoli