I don't have my notes handy, but IIRC there was some speculation that they would control too much market share in instruments- so likely the FTC would extend in order to get concrete data, which takes more time than usu HSR review.

Re:EU. Usual legal strategy now seems to be to have the dominant regulator (US/EU) with interest in the merger go first, then hope the 2nd will pass it quickly.

Just a guess, and it did not work well for ORCL/JAVA. I'm using a pencil and guessing 12/09 myself to close. GL, AT.