They haven't been released yet. They are essentially like an AimPoint, but aside from the tritium illumination, and based on the pre-production models, they are far behind the AimPoint in usability and durability, and cost much more as well.
Given the incredible battery life of the current AimPoints, and the fact that they use cheap, available lithium batteries that have a super-long shelf-life, reliance on batteries is no longer an issue. $30-40 will buy you a 10+ year supply of AimPoint batteries, which are good for 10+ years in storage.
The TriPower uses a plastic body, has poor battery life, requires a blue-filtered lens, and is needlessly complicated. It's one of those ideas that sounds good on paper, but isn't great in practice. And Trijicon is having a lot of problems getting it right, which is one of the reasons for all the delays.
(Note: I'm a HUGE fan of Trijicon's iron nightsights and the ACOG scope lines, but the Reflex and TriPower just don't cut it.)
-Troy