[COLOR=black]Nope. They didn't even should up at E3 to talk about it. However, I here that the release date will be longer than HL2 to Ep1 and Ep1to Ep2...so...don't hold your breath[/COLOR]
They're more worried about Left 4 Dead 2 than making Half-Life 2: Episode 3...
Gordon may have been asleep for 20 years, but he was in a stasis somewhere in another universe, he's still 27 in physical appearence but in actuality he's 47, so if Alyx and Gordon were to get together the age difference wouldn't really matter anyway.
I believe that Gordon swallowed a bottle of bleach as a small child, when rendered him unable to speak.