Empire At War is in for a Fall (Q4 - Quarter 4) release. Galactic battlegrounds was released in November - on time when it was announced in the February of that year.
EaW is looking good at this early stage and I believe they have been working on this engine and Lucasarts for some time - almost 2 years on this.
I interviewed SWGB Game Director - Garry Gaber who used to post on our forums and he mentioned that he was working on a 'related project' to SWGB and it wasn't an expansion. Now we have EaW. Sadly, Garry has left Lucasarts - looking after his baby and family (wish them all well) but with the history in mind, a Q4 release does look extremely likely