They made an announcement today, but didn't say anything specifically about the Golden Age shorts. My guess is that the old Disney Afternoon and Disney Channel originals are going to be a higher priority, along with the full length animated film catalog before the shorts become available. But I do think we'll probably get them all eventually.
Warner is also launching their own streaming service by the end of the year, and their latest announcement (from February) specifically mentioned both Looney Tunes and Bugs Bunny. My guess is that the Boomerang streaming catalog is going to be rolled into the Warner service, and they'll continue to add more shorts on occasion, as they have on the Boomerang app, until most of the Looney Tunes, Paramount, and MGM catalogs are on the service.
That said, with both Disney and Warner, I'm not too sure they're going to be in any hurry to release older black-and-white shorts, but between the two, I'd think Warner will be more ready to do it. Their press release also mentioned Casablanca, and that the focus would be to first get the back catalog on the service before diving into producing original series (basically the opposite of Disney's approach). From my reading of it, it looks like Warner wants to basically put all of TCM, Cartoon Network, Boomerang, and the DC Comics universe online, along with their more recent movies and series ("Friends" and LOTS were properties that were mentioned specifically). So I'm hopeful that the entirety of the Looney Tunes, Paramount, and MGM cartoon catalogs become part of that--I'd love to see the Buddy cartoons in decent quality!
NBC Universal is also supposed to launch their own streaming service in the near future as well (yeah, there's about to be a saturated market). I don't know what their plans are, but I hope that it means we'll get the Lantz catalog online, too.
These companies seem to consider the home DVD/Blu-Ray market just about dead, so I think this is going to be our best chance to see a lot of this stuff in upgraded quality, since they're not going to get released on DVD/BR anytime soon. I'm hopeful, but I'll take a wait-and-see approach.