We used Sikuli for test automation in a pretty large project with a Windows UI. Got kicked off by a TeamCity agent for every build and worked really nicely.

Thumbs up.

You do need to be careful about timing and getting the right images so tuning things to work under all conditions is a bit of an art. Also being able to recover from a failure so you can continue testing is another bit of art.

As to why this is news there seems to be a new release out (or soon?) 1.1.0 ... Sikuli development seems to have almost died a few years back but it's made a comeback over the last ~2.5 years which is nice.