Over at comic book resources there's news about Ultimates 3 Issues #1-3 being collected in "March On Ultimatum". My guess is that it's the first of two collected editions... yet there are only two issues left so I don't understand why they wouldn't wait to collect all five issues... then again, they're probably just milking the sales some more.
Here's the details,
ULTIMATES 3: MARCH ON ULTIMATUM (APR088026)
Written by JEPH LOEB
Pencils & Cover by JOE MADUREIRA & CHRISTIAN LICHTNER
Parental Advisory …$4.99
On a side note I have no idea when Ultimates 3 #4 and #5 will be released, they seem to be delayed.