Yes, there are still lots of clients running 2007 and Microsoft is still pumping out those non-regression-tested CU’s for it.

More details about the updates:
http://support.microsoft.com/default.aspx?scid=kb;EN-US;2553022
http://support.microsoft.com/default.aspx?scid=kb;EN-US;2553020

After the patch, don’t forget to run the PSCONFIG to update the farm.  While most of the time this works fine:

PSCONFIG.EXE -cmd upgrade -inplace b2b -wait -force

My favorite is this:

PSCONFIG.EXE -cmd upgrade -inplace b2b -wait -force -cmd applicationcontent -install -cmd installfeatures

Because it works every time.