It seems Hisanori Takahashi will be granted his release after talks with the Mets failed to reach an agreement. Since Takahashi will no longer be able to negotiated with the Mets until May 15th, he will need to move on to find another club. Takahashi is said to be looking for a 2-3 year deal at about US$4-6M per year. It seems the Mets were only willing to go one year guaranteed at about 1.5M plus incentives.
Hideki Matsui and Hiroki Kuroda were included in Ben Reiter's Top 50 Free Agents. Kuroda was listed at 15 with a best fit with the Mets; Hideki Matsui 37th with a best fit with the Mariners.
A designated hitter who might be available as a free agent, especially if the Angels sign Crawford, is Hideki Matsui, who would be perfect for the Tigers' DH void.
Another Nikkan Sports article mentions that it might be a while before Matsui finds a suitor, especially with players like Carl Crawford and Jayson Werth also on the market.