The folks at TenTonHammer experienced Global Agenda hands-on at Pax 2009 in Seattle, and left this writeup.

A quick excerpt:

While my time with Global Agenda was somewhat brief, I walked away impressed with how polished the gameplay felt even at this stage in development. The controls felt extremely intuitive, and although combat can certainly be slightly chaotic when first hopping in, it didn’t take all that long to get a feel for the role of your class in a given scenario or even for some of the game’s more tactical elements to become much more apparent