I've just recently purchased an Xperia X10 and have been playing around with it, trying to get it set up correctly. I came to the realization that it was lacking a number of the google based apps, most importantly the app store on the Google play website. After some digging I found myself a copy of it and installed the app, but still couldn't access the store as it required an account to be set up with my google credentials.
I've got a Gmail account all set up, ready to go, but for whatever reason when I try to add an account to the phone none of the expected account types are available. At the moment, only 3 account types can be added: SyncML, Exchange Active Sync, and Sony Ericsson Sync. I tested a few other apps, some google based plus the facebook app and none of them seem to update the link / accounts list to join up the app with an account. I checked permissions on the installed apps and they all look in order. I checked for settings inside the accounts & sync page, but to no avail. I have tried uninstalling / reinstalling the apps, and that yielded no results either.
I'm about at the end of my tether with this, if anyone can think of something I'm missing I'm all ears.