Following up on this post, I’ve confirmed that the story in the Post is wrong and Eisen is still the White House ethics czar. See also this follow-up post at a Foreign Policy blog, which gives more details as to the controversy that is the basis for Sen. Grassley’s hold, as well as some of the details for the termination:

Not all Senators share Grassley’s contention that Eisen’s role in the Walpin affair remains unsettled. In a June 2009 letter (PDF) to President Obama, Sens. Joseph Lieberman (I-CT), Susan Collins (R-ME), and Claire McCaskill (D-MO) wrote that the administration had proved it met the legal requirements for notifying Congress when an inspector general is removed.
Eisen’s allies are also circulating this parody newsletter created by Walpin as evidence that his behavior warranted his termination. In the fake newsletter, Walpin wrote satire news announcements that some saw as inappropriate, such as an item “reporting” that former New York Governor Elliott Spitzer was a leading candidate to head the Office of the Inspector General’s procurement shop.