Though it wasn't announced at the Grammy nominations, a re-united Beach Boys will be appearing at the Grammy's next year, just in time for their 50th Anniversary. I don't know if this means Brian Wilson will rejoin his band for a tour. Part of me hopes so, part of me worries it will push him over the edge. The man is fragile, and he doesn't want to do it, but, as he noted earlier this year, business concerns might take precedent.
Al Jardine has been talking to Rolling Stone, saying (what is left of) the original Beach Boys are entering a studio later this December, though I doubt they will be recording new material. This is probably just to rehearse.
As long as Brian is there it will be a Beach Boys re-union, but without his late brothers, Carl and Dennis, it won't be complete.