Depends on you. Personally from when you've played last, it is worth it. If you're a player that quit about 2 months ago, and then suddenly come and ask if its worth it, I'd say no since there wasn't anything really new. From the time the Hero Mode patch came out and now, there has been some good amount of stuff released, such as new guns, maps, etc. We also recently got a new mode: Zombie Mode. It was released on September 15th as far as I know.
That's a gameplay of Zombie Mode. It is long, but naturally one game of Zombie Mode is as long.
Also, like I said, we got a few new guns, such as DSR-1 Camo, M4A1 S-Patriot, Ruger(don't remember the entire name), Scar Heavy Camo(New weapon worth 8900 BP).
There is more out, but those are the ones I can think from my head at the moment.