The open-source version of Chrome OS, Chromium, has received its first GPU acceleration today through the custom variant Flow. It now supports hardware acceleration through an NVIDIA Ion chipset and should get both basic support as well as added performance in those areas that can use the faster-than-usual graphics. Battery life has also increased and is matched by proper support for automatic updates.
The specialized Chromium build can boot entirely off of USB and needs a 2GB or larger flash drive if it isn't installed on a computer's own hard drive. It's not said if the improvements made to Flow will be rolled into the main Chromium OS branch. Google is unlikely to add Ion support into Chrome OS itself as it already has strict requirements for which hardware will work with the platform, although it may still get GPU support as it software has referenced NVIDIA Tegra processors.