Talking at the BAFTA Games Awards 2013, he said to expect it to be revealed in about "a month or so", around the time of the Game Developers Conference and PAX East.
While Solomon didn't provide specific details, the mention of PAX East suggests possible playable content to show at the public event, meaning possible DLC or expansion content.
He added that the game is something that's going to be "committed to over the long term".
Solomon previously revealed that it is working on "something really awesome" for the game in 2013.
XCOM: Enemy Unknown has already received two DLC packs since releasing in October.
Last night (March 5) XCOM: Enemy Unknown won a Games BAFTA in the 'Strategy' category, one of the few retail titles to pick up an award on the night.
Dishonored came away with the coveted 'Best Game' prize on the night, but Journey dominated throughout, winning five of its eight nominations for 'Original Music', 'Artistic Achievement', 'Audio Achievement', 'Game Design' and 'Online Multiplayer'.
Other big winners included The Walking Dead and The Unfinished Swan, which received two awards each, while Far Cry 3, New Star Soccer and LEGO Batman 2: DC Super Heroes also walked away as winners.
Elsewhere, Valve co-founder Gabe Newell was inducted into the BAFTA Fellowship for his services to the games industry.
Host Dara O Briain had previously described this year's nominees as like comparing apples to oranges.
> BAFTA Games Awards 2013 winners in full
> BAFTA Games Awards 2013 live blog as it happened
Watch Jonathan Ross, Russell Kane and BAFTA winner Danny Wallace discuss what games they've enjoyed in the past year: