Problem is how does one identify a batch as "new"? If by sell date, then the answer to your question is YES.
I think my 7D & 5600HS is one of the newest pair in this forum as lately most people have been buying the 5D. Bought my 7D in Melb in late Sept 2005 and 5600HS in SG in mid Oct 2005 and both didn't quite talk the same language. Sent both to KM Oz for recalibration in Nov and now my flash exposures are spot on :thumbsup: .
Some people (eg., sulhan) have no problem from day one, and a lot of people just got used to its nuances and compensate accordingly. Me ... was too lazy to have to remember everytime ... also perfectionist ... want everything to work exactly as they should. As both were still under warranty, recalibration was free. Just had to go without my 7D for a week :cry: .
Calibration is free if your 5D/7D and 5600HS are still under warranty (at least it is in Oz). Oz turnover time for me was 8 days from the day I posted my 7D+5600HS to Sydney to receiving it back via courier.