A couple of Mega Man ZX manga related updates coming from Amazon.com:
Volume 1 received a small price drop over this holiday season, marked down from $13 to $10.36. The book is still on-track for a March 29, 2010 release, but with UDON, you never know.
Meanwhile, Amazon has opened up a pre-order page for the second, and final volume in the series. Volume 2 is looking to release five months after its predecessor, slated to release July14th. A bit of a wait, but I'm sure UDON's other upcoming Mega Man books will keep you busy 'till then.