The hours that were posted originally were typical for January, but with all this talk about MLK weekend being booked solid, they may be opening up that Friday and Sunday night a bit. But I wouldn't count on it.
I know a CM told someone that the Friday check-in on MLK weekend is a record breaker, but I really find that hard to believe - unless there are some major competitions coming down for the weekend (i.e. cheerleaders, dance, soccer). But if it's true, and they open the parks later, that's good!
IMO, The new Disney site is lousy, and hard to navigate!