Jump magazine (via Tales Source) has revealed that the next entry in the Tales of series is set to be announced at this year's Tales of Festival in early June.
The Festival itself runs from June 2-3 which isn't too far away (and right ahead of E3). The new game is simply listed as the "Next Tales of..." without a platform or release date, similar to how Tales of Xillia was revealed a couple years ago.
With Xillia's success it's possible the new game is a HD title as well, or at least we hope so. Stay tuned.