1.1.1 was major changes to several mods as detailed in the changelog here. 1.1.2 was mostly minor bugfixes (console indicates updates to SecretRoomsMod, Immibis and ChickenChunks on startup.) From what I can see, the major changes include the new version of Thaumic Bees (adds Minium Bees and mineral bees), the new version of GregTech (changes the behavior of the IBF, the Fusion Reactor in a major way, the crafting of circuits, the usage of ingots, and maybe more) the new version of Factorization (any and all shapeless recipes can now be made in a Mixer; yes, it's silly, but whatever), and some minor stuff with most other mods, including possibly breaking a few things with SecretRoomsMod textures/functions and the adding of new Advanced Solar Panels item textures.
The unofficial wiki hosted at feed-the-beast.wikia.com was our earlier form. It's fallen into considerable disrepair from what I can see, which is unsurprising as most of the people who were/are major contributors have now moved to this wiki, ftbwiki.org. The official wiki is mainly updated by two people, who are (last I checked) focusing on adding template documentation and not adding information to the pages. Much has changed since we moved from Wikia to our own namespace, such as many new articles being added here that don't exist (and probably won't exist now or in the foreseeable future) there.
Once you have a ftbforums account, you should be able to log into the wiki or be logged into the wiki if you are logged into the forums. I'm not sure what your problem could be, unless you have a special character (i.e. anything except numbers, letters, underscores or hyphens) in the name that you registered with, as I've heard that such things have previously caused problems.