I am currently working through the core plus deck. Core2000 done, Core6000 about halfway, most of the JLPT vocabulary done except 2 and 1 still 2800 cards. Though I did other things before, Kanji Odyssey for instance and that one helped immensely. As far as websites are concerned, and because I am mining constantly from both the web, as well as books, I got way more but still far less than needed to fully comprehend books, or on a very high level and without constantly marking new words. The same with videogames, though I get better. I can't comment on Manga, as I haven't read any, they are not my genre I guess. Websites, News, Fashion and such are no problem, some Anime I can watch and understand almost everything,
http://www.dailymotion.com/video/x98r38_...shortfilms 笑ゥせぇるすまん for instance. Or things like this
some Podcasts and Daily talk on radio are relatively easy, too.
But there is yet so much more to learn, to fully comprehend things thrown in my direction or things discovered at random. And this will take even more effort on my side, and a Core or whatever deck, is by far not enough to reach it. It is what else one does besides it that lets you progress. So read while you are doing any of those decks, even if you don't understand, listen and get used to the language, this is what will get you far in the long run.