It's all speculation, but I would say the search box getting larger (so as to look like Quora) does mean something, as in they might be pushing for search, which would be interesting.
yeah, the Quora idea is quite possible. Where search drives the interactions. As I wrote, search is something that’s totally under-realized on the Facebook platform. There is no way to search and filter content.
Maybe they'll roll out a HUD like the next version of Ubuntu?