No further information will be released until then, the invitation states. It's a good guess of course that he's going to announce his bid for the GOP nod for governor.
Expect his entry into the race to shift the grounds of the GOP primary a bit. Domenici, Jr. -- as in the son of Pete -- has a lot of name recognition, and likely can be very competitive with other Republicans in terms of fundraising.
(On that note, Susana Martinez announced today that she's raised $162.046 since last October, and $305,723 to date.)
Given it's this late in the race -- with the primary in June -- it's likely Domenici, Jr. has some polling or other research showing he's got a good shot. Don't expect too many other entries into the race after this.