In a surprising move, the Under Secretary of Commerce for Intellectual Property and Director of the USPTO David Kappos is considering extending the US Provisional Application pendency from one year to two years. See http://www.uspto.gov/news/pr/2010/10_10.jsp
I find the idea a little crazy. In the US the patent currently goes to the first to invent, not the first to file, and one can use the provisional filing date as pretty good indication of when one had the invention reduced to practice as described. Elsewhere, one assumes the Paris Convention would apply and so priority could not be claimed from the provisional in other jurisdictions.
Seems like a non-starter.