Groping Eels has been replaced with Unbreakable Grasp.
Unbreakable Grasp offers tons of protection and utility - 80% reduced movement speed slows most enemies to a crawl. It might as well be a root.
Getting straight to the point, the answer is yes, it's better than Groping Eels. Though, I do feel the two skills are balanced enough so that Groping Eels is far from obsolete.
Here are my reasons for preferring Unbreakable Grasp over Groping Eels:
-It is applicable in more situations than Groping Eels. I feel this move will be more beneficial to you and others in your party than the straight damage buff of Groping Eels. It allows you and your party to set up on enemies very easily and concentrate damage in an area for the entire 8 second duration. I had a very fun experience with a Demon Hunter. I would snare a group of enemies and we would both fire missiles into the area of effect while the enemies stood there. The Barbarians in the party were not as impressed, though it was useful for keeping Barbs from getting swarmed or damaged from Champions with mods such as Knockback.
-Everything becomes much easier for a party which can reliably avoid damage and flank enemies. Enemies with high HP usually move more slowly by default. With Unbreakable Grasp, Unburied will be almost completely ineffective against you unless they have the Teleport ability. Unburied at full health usually stay within the AoE for the full duration, taking heavy damage DoT damage and many times not even hitting other characters. Champion Carrion Bats and Scavengers with increased movement speed are suddenly a lot more manageable.
-The skill has beautiful, blue glow. If you use this alongside Haunt, you will find that there will be pillars of wispy, blue spirits rising up from all over the screen. This is much more aesthetically pleasing than the foul animations which accompany Groping Eels.