Decided to root the tablet(acer iconia tab a500) before an update happens and makes it difficult.
Basically with my previous honeycomb version's it was not possible..
Now that i have ICS almost all the old rooting methods are supposed to work. i used the one by blackthund3r at this link:
Instructions(in brief for full details go to the link above)
On Windows(for linux go to the link above)
0) Install ICS on your tablet(see my previous post about this)
1) Enable USB Debugging on your tablet (Settings | Development | Enable USB Debugging)
2) Plug your tablet into the computer using the USB cable(make sure you install the latest drivers first, from hereabout 90mb)
3) Load up ICS Root(from here or the link above), choose your options and press "DO IT!"
4) Once rebooted, enjoy!!
was fairly straight forward.. got done in 5min.
note: this method apparently works on Acer Iconia Tab A500 / A501 / G100W / A510 / A511 / A200 (probably) on stock Ice Cream Sandwich 4.0.3 from Acer (either leaked or OTA)
blackthund3r also has an Un-rooter app at the bottom of the page.. incase theres an OTA update later that doesn't install or something, and you feel that your device being rooted is somehow the issue.
heres another method to root this tab
incase the above method didn't work.