Xperia Play is now the longer the only PlayStation certified Android smartphone, at least in Japan. Sony Ericsson has started rolling out an over the air update starting today Arc users in the country, which will enable the PlayStation Certification meaning you will have the access and compatibility to 100s of games that were only available on Play till today. However the actual content in PlayStation store will not be available before December.
This update will also takes the Android version to Android 2.3.4, POBox 4.3, news widgets, Facebook Inside Xperia 2.0, Native screenshot functionality, Xloud, 16x Zoom support in camera, and Wireless tethering.
More on update for Xperia Arc here
A similar update will also be rolled out for Xperia Acro from November 15, which will also enable PlayStation certification for the device along with most of the above mentioned updates.
More on update for Xperia Acro here
If you cannot wait for the OTA roll-out, you can update your devices now via the PC companion software, the update via PC is already available from November 7.