Team Cyanogen just released Cyanogen 9 Alpha 0 for the HP TouchPad rocking the latest and greatest Android 4.0 Ice Cream Sandwich. Some kinks need to be worked on are hardware video (Youtube HD versions), the camera, some market and google apps and audio.
They have previously released Cyanogenmod 7 Alpha 3.5 for the TouchPad which was stable from my experience. This release obviously has rough issues but most of what we know on ICS works.
If you have a TouchPad and want to install Ice Cream Sandwich, please take note that this is an Alpha Zero build. and as they say in their RootzWiki thread, the zero means “zero hardware-accelerated video”, “zero camera”, and “zero support!” so install at your own risk.