There is a story on Grandprix.com that there is a possibility that one of the current teams will not be present for Silverstone due to financial reasons. Minardi is not the team in question by the way. I would think it would be Arrows because the team boss put $4 million into the team to continue - e.g Tom Walkinshaw paying Ford out of his own money to continue.
I really hope this does not happen. I hate to see any team retire from F1 due to financial reasons.
The link is
http://www.grandprix.com/ns/ns06555.html