According to MLBTradeRumors.com (and Ken Rosenthal, via Twitter) the Astros and Marlins have agreed to a deal sending Matt Lindstrom from the Marlins to the Astros. Who's going back to the Marlins? No word yet. Really, the only word is that medicals are being swapped (though Lindstrom's agent did tell him to hold tight).
Not sure how I feel about this YET, but he has closing experience (he had 13 saves in 15 opportunities last year before injury) and he is cheaper and younger than both Valverde and Hawkins (either of whom could have come back and closed again this next season).
Will have more insight once it is 100% completed and I know the other parts involved.