The Senior Product Manager for the BlackBerry PlayBook at RIM is departing. Ryan Bidan, according to postings on his Twitter, is apparently headed to Samsung. There is no word on who might be replacing him, and publicly RIM has only confirmed that Bidan has left the company.

It is unclear as to why Bidan left, but he will apparently become the Director of Product Marketing at Samsung. Bidan will join fellow RIM alum Brian Wallace, who quarterbacked RIM’s digital marketing efforts in the move to Dallas.

We see the changes as a big period of transition for RIM. Like most analysts, we think that RIM has a lot of competition to deal with. Hard to say if these are the last of the departures, but more people leaving would not surprise us.