I still play this a fair bit, just got back into it with the latest Issue update.
Not a very active EG member, more a lurker, but I have an SG which has been around since the EU beta. The longevity comes in new characters and teaming with friends.
I can't stand any other MMO, bar my stint at uni on Planetside. Tabula looks intriguing, as do the Star Trek and Stargate online games. Guildwars was nice, with its story and progression, but the instancing, lack of movement, the fact levels didn't stop aggro against you and the incessant need to upgrade all the time.
COH is great with it's Sidekick system, even the new auction house/invention system is nowhere near as annoying as the trading/need to upgrade in other MMOs as you can function perfectly well using the standard enhancement system, without touching the trading/inventing at all.
Auto Assault got boring quick as none of my SG tried it also, people you know really can make the difference. I won't list the SG address here, save me being accused of soliciting

, but if anyone's interested, reply or PM me.