Looks as if a third Mega Man graphic novel is coming down the pike. According to Amazon.com, Mega Man Megamix volume 2 is slated to ship out on May 14th, 2010 -- a mere three months between volume 1's release (Feb. 13, 2010). Given the fact that Udon's recent MM books have seen their fair share of delays and bumps, this release date is most likely subject to change.
On a related note, LilFormers has posted the English cover art for Mega Man Megamix volume 1 and the upcoming Mega Man ZX graphic novel:
From the looks of it, they're both practically identical to their Japanese counterparts. No complaints here!