I read the thread regarding the lack of HD broadcasts on Comcast California for U-Verse customers last week, and made a mental note to ask my sister about it.  She works for AT&T and is involved in selling U-Verse service.

She had a meeting with a Senior Vice President yesterday and brought the situation up and also forwarded to him the AN thread about this.  She received this email back this morning:

"Got some good news for your inquiry about the A's.  Great question.

  The A’s games are carried on Comcast Sports California HD. It has been an issue for us in the past but we just received some great news this morning. As of 8am, that channel has been added to the U-verse line up, and our customers will now be able to see the A’s games in HD. "