From Google’s Webmaster Central:
We just added external resource loading to our Flash indexing capabilities. This means that when a SWF file loads content from some other file—whether it’s text, HTML, XML, another SWF, etc.—we can index this external content too, and associate it with the parent SWF file and any documents that embed it.
This new capability improves search quality by allowing relevant content contained in external resources to appear in response to users’ queries. For example, this result currently comes up in response to the query [2002 VW Transporter 888]: