After some discussion with Christina Stiles, Odyssey Prime's line developer, she and I have decided to take Odyssey Prime in a new direction. As of December, we will have access to a True20 license and so will be switching out the game's Unisystem aspects in exchange for this new rule set. The d20 Modern portions will also remain.
Currently our plans are to release a new v2.0 rulebook in 2008 that will include both the d20 Modern and True20 rules. If you've been playing the d20 Modern version already, your gameplay will in no way be affected, and your existing rulebook will remain 100% valid. If you've been playing with the Unisystem rules, unfortunately your existing product will not be supported in the future.
There are various reasons for doing this change, and I know Unisystem fans will be disappointed, but Christina and I both agree that if the line is to see any more releases, we need to consolidate our control over its future by bringing it back entirely in-house.
If you want to get your hands on the Unisystem/d20 Modern version, you can find copies in print until the end of November.
Hardcover $40 http://www.lulu.com/content/245503
Softcover $30 http://www.lulu.com/content/228405