To the best of my knowledge, there have been no significant developments in the continuing saga of "who is blocking the science nominees in the Senate". Progressive Alaska's Philip Munger noted in a comment here that Senator Mark Begich's (D-AK) office says Begich is not involved, and that he has received additional information pointing to David Vitter as the culprit. Meanwhile, Talking Points Memo's Elana Schor reports that she's received denials from both Jim Inhofe (R-OK) and John Barrasso (R-WY) - and that's in addition to the denial she received from Vitter yesterday.
In the absence of information, the only recourse for those of us interested in trying to push this issue forward remains contacting our own Senators and the office of Senate Majority Leader Harry Reid. (Contact information for those folks can be found in my earlier posts on the topic.) As I've said before, it's important to keep pressure up on this. Anything you can do will be helpful.