FOOCH'S UPDATE 11:40am: Well, bad news got worse (thanks to PHUT for pointing this out). Singletary is saying it's a fracture in the right shoulder and Jones is now out for 8 weeks. That basically means he could be back the first or second week of October. With Bruce and Morgan starting, Hill as the #3, and Crabtree holding out, Dominique Zeigler and Arnaz Battle are both looking like good bets to make the roster. Heck, even Micheal Spurlock has seen his chances shoot up.
Thanks to Maiocco and Barrows for Twitter updates on this. I'm guessing they heard this from the 49ers PR folks. According to both Brandon Jones' shoulder injury from yesterday will keep him out two weeks. Maiocco referred to it as a shoulder sprain, Barrows referred to it as an AC sprain. Based on the schedule, he could possibly get back for the Raiders game two weeks from tomorrow.
Maiocco mentioned that "Arnaz Battle has a chance to step up and earn a 49ers roster spot." I tweeted a reply to Matt asking if it would actually be a battle between Dominique Zeigler and Battle, or if Zeigler was destined for the practice squad. If/when he replies I'll update this post.
This is definitely bad timing for Jones' injury (not that there's such thing as a "good time" for an injury). It sounded like he was playing really well and showing solid chemistry with the QBs. I recall Bryant Johnson going down last preseason with a hamstring injury that lingered into late August. Once he got back, it took him a while to get back in sync with his QB. Of course he also had other lingering injuries, so let's not get ahead of ourselves. If Jones can get back for the Raiders game, he should have plenty of time to get it in gear. At this point I'd assume Isaac Bruce and Josh Morgan will be the starting wide receivers. Not a big leap, but still worth noting.