An Acer spokesperson has confirmed to me that the Iconia Tab A110, Iconia Tab A210, and Iconia Tab A510 will all be upgraded to Android 4.1 at some point in the future.
No specific timing info is available just yet.
UPDATE [10/5/12]: Acer now tells me the Iconia Tab A210 and A510 upgrades are scheduled to take place within this quarter, before the end of 2012. The Iconia Tab A110, meanwhile, will actually ship with Jelly Bean preinstalled, so no rollout will be required.
The Iconia Tab A700 is also on the "yes" list; that device's upgrade actually started rolling out last week, according to numerous user reports. Officially, Acer says the A700 rollout is set to kick off in full swing during the third week of October.
Now for the bad news: Acer says its Iconia Tab A100, Iconia Tab A200, and Iconia Tab A500 will not be receiving Android 4.1 upgrades. In other words, if you've got one of those tablets, your current level of Android is as high as you're gonna get (in terms of officially sanctioned rollouts, at least).
Acer has typically done quite well when it comes to keeping up with its upgrade promises. The company got an "A" in my recent Q3 Android upgrade report card. It received similarly high marks in my reports for the previous two quarters as well.
Remember, you can find the latest Jelly Bean upgrade info for any device in my Android 4.1 upgrade list. It's always kept up-to-date with the most current details available for all phones and tablets.