Yes, it is alive. Playing on League side tho, so I do not have information either on IMP side.
However, pretty much there is more than enough content for each side, as I experienced.
To be fair, todays' MMORPG standards are mostly instanced content based. Even todays WoW feels like an empty map. It's true that you can feel it had rough times, and requires more players, but just join in one of the faction main guilds, and have fun with orthers. You will mostly do grouped content in the end with your guildies only anyway.
Have fun, if you decide to join us!