In Metro IE, Adblock Plus' filter list is called out and set up through the Privacy setting. Adblock Plus maintains the list of the most common active ads. Metro uses it to block these active ads. It really is an Adblock Plus add-on in the classic IE/Firefox sense, MS just renames it TPL and puts it under their privacy setting, and they do away with the term add-on altogether, is all.
Go to Settings/Privacy and click AddTrackingLists. Pick one of the Adblock Plus'Tracking Protection Lists (TPLs), either EasyList or EasyPrivacy.
Big difference in speed. Try it on websites with tons of ads like XDA or ESPN. Backward and forward paging seem much improved with AdblockPlus on.