Tiberium Odyssey for these reasons:
-its done by a lot of great modders so it has to be good
-new terrain
-new gameplay modes specified by maps i do believe
-great looking buildings and units
-TitanMarkII might kill me if i vote otherwise
and everything is known to be good quality to
although i hate to not vote for TS Squared (yeah sorry i dont see anything that does show the subscript thingie) seeing as im doing some work for it but TO just looks that good.