Didn't really want to do this but, it does represent a key element to the game and the AI does like using them as well. Because of budget constraints it's more about improving and extending life cycles on current equipment and maintaining or developing one's own defense infrastructure. Few are doing anything with new equipment though India does come to mind with their new attack helo.
My first entry is the improvement on South Africa's ROOIVALK which was grounded last November (Entire fleet.) due reliability concerns. In fixing the reliability issue they also included upgrades to it's avionics and fire control systems.
http://www.defpro.com/news/details/18049/
We are currently seeing the deployment of tank munitions in target selection as I noted on the MBT thread with the IDF and Germans so this next weapon is a natural progression of that trend for AH's. HELLFIRE II.
http://www.defpro.com/news/details/17913/
Regards,
Pat