Was told by an AZ Pivot dealer that the Mach 5.5 is now discontinued. I guess selling mine last week was prescient! Seems like a 29er version of the Mach 5.5 would be the next offering and would combine the Switchblade and M5.5 in the new design look, and would slot exactly between the Trail 429 and the Firebird 29. And the last three Pivot releases were all 29ers. Throw us a bone John P!