I have not seen any kind of DPS meter addon, or a external like ACT for EQ2.
I for one hope they never come up with a damage meter for Lotro. They tend to vary widely in the way they parse and in the same raid same players same everything two meters can post different results even from player to player. Unfortunately, folks tend to rely upon them to measure actual player skill too often. I play wow as well since it came out and tbh meters ruined the game imo. My guild is in the top ten in terms of progression on my server I raid regularly successfully while I don't "top" the meters but occasionally, I do respectful dps.
Having said all that I still find the meter mindset one that number 1 means nothing about being a good raider, number two is misleading as you can have the highest dps by just dieing in the fire earlier then your raid mates, number 3 causes more wipes when you have people paying more attention to them then what they should be doing in the encounter.
While everyone works to be a contributing member of a raid team the meter maniacs tend to be those who care more for the rush of beating everyone else rather then actually downing the bosses to those who go further and post "meters" everywhere (of course only the ones they happen to top at the moment) in order to somehow claim superiority.
Lotro for me is an escape from such foolishness and feels more like genuine team oriented playstyle.