So after some random glitches with Steam thinking that LOTRO is still open when it is in fact closed when I try to quit Steam, I decided to verify the game cache of LOTRO.
Well...I did this and it said 48 files needed to updated. Okay, no big deal - then I looked at the download and the total was 11.9 gigs! That's a lot of space for 48 files!
I wonder if there was anything truly wrong with my client (I've had no issues, no mods, nothing - just a vanilla Steam install running happily for months) or if I'm getting newer content that wasn't DLed from the standard launcher already?