The latest release is shown here, however be warned that is an Enterprise site not consumer and just because a DAT appears there doesn't mean that it should instantly appear on any particular machine. DAT's take quite a while to filter through to all servers and in some rare cases, are cancelled for whatever reason, so don't get worried if you are one or two behind what is stated there. If SecurityCenter says you are up to date then you are.
The newest product not yet generally released uses a different update method and you wont even be able to see what DAT is being used in your software, so when and if your software updates to it, don't panic. ;-)