Yes, certainly it works - we've installed MSI's generated off our BizTalk 2009 / VS 2008 environments directly onto BTS 2010, including retention of the 2009 binding files. The BTS 2010 environment was a multi-server clean install.
In fact, many of our incumbent, stable BTS 2009 apps are still running on our BTS 2010 prod servers - we haven't bothered to rebuild them.