Ive been dealing with this bulls-h-i-t for over a month now... it's what I call 'hiccup' lag.
Essentially, I bounce back in physical space to where I was a second or 2 ago. I'm still facing the same direction I was at the moment I bounce back, but I lose all my momentum. It happens constantly every 8-10 seconds.. non-stop. SO, I walk off cliffs, fall off bridges, fail jumps across gaps that I've just cleared, and constantly find myself getting stuck in spots I can't get out of or be rescued from (like the lava lake under the Demon Queens Court). I've jumped and tumbled thru or past enemies, snuck past them, or jumped over them, only to suddenly be back in the middle, and with no momentum, I get crowed pressed and trapped.
It god-a-m-n sucks
Seeing as how I'm an Arti.. with a real need to keep distance between myself and my foes.. its a constant death-sentence, only postponed thru shear chance and dumb-luck the whole time I'm playing
PS: REALLY wish maps would stop expiring just because I don't run an area every day. make it hazy if they have to, but once I've traveled something in a life.. I should be able to keep the info