You just have to know where to look. I've been running ICS for months on my A501 and love it.
Since ICS, I've been sticking with TegraOwners ROM ( http://forum.tegraowners.com/viewtopic.php?f=9&t=370), which will be updated to version 171 within a couple of days. This will include an updated kernel and other updates for this custom ICS rom.
Thor, one of the main Devs, has posted that they are going to wait until CWM drops (releases) Jelly Bean source, before they go to work on a custom A500/A501 JB ROM, but is will happen. The TegraOwner's rom is built on top of ClockWork Mod. In fact, the current ICS (4.0.4) ROM includes CWM version 9!
A rooted system and Thor's Touch Recovery version 1.7.3 are needed to install the ICS ROM.
To Folks waiting on Acer for updates:
Why wait on Acer? Dev's do a better job than Acer anyhow.. and do you think Acer is going to release a JB ROM for the 500 series? Sure, you will have to learn a little bit and you want to be careful, but it is not that hard to flash a custom rom, and it sure beats sitting around pissing and moaning about Acer and the carriers. IMO.
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