Reports say that AUO will start shipping 4.3" qHD AMOLED panels next month in June, and will supply panels to both Sony and HTC. HTC will use those panels in their One S smartphone. The One S currently uses a 4.3" qHD Super AMOLED display, which is a Samsung trade mark, so it's not clear how they will handle two suppliers.
SMD will still be the primary supplier of AMOLED panels to both companies, and currently the quality of the SMD panels is still superior to AUO's ones. Indeed the reports say that AUO suffers from very low yields (around 20%) in their first AMOLED 3.5-Gen line in Taiwan.
AUO plans to invest around NT$40 billion (around $1.3 billion US) in 2012, mostly on AMOLED panel development and other advanced technologies. Earlier reports suggest that AUO is collaborating with Sony while other reports say that HTC secured AUO's entire OLED capacity. Perhaps the truth lies somewhere in the middle...
