Okay so he had more tact than that:
"One bit of business for those of you going to the premiere tonight: There WILL be a tag at the end of the credits on Guardians of the Galaxy, but it won't be playing tonight, just as it hasn't been playing on the press screenings. It's something we're saving for people who go see the movie on the first day in theaters around the world."
So, the good news is, we have confirmation of a Marvel movie tradition, an after movie scene during (or at the end) of the end credits. The bad news is, we son't get a good description of it (for those who cannot wait). Well, it won't be long now…
In other Guardians news, James Gunn mentioned on Adam Carolla's podcast (starting around the 52:40 mark), that if Guardians of the Galaxy does well, he will be back to direct the sequel.
To tide you over until August 1, when the movie finally arrives, here's a behind the scenes IMAX featurette!
Updated to note:
Update #2: It sounds like the end credits scene might be adding something new to the Marvel Cinematic Universe:
Also, if there is to be a Guardians of the Galaxy sequel, like Avengers, Kevin Feige muses that the roster of the Guardians may change/expand:
And it seems they have thought about a sequel:
Could this be a small hint about who might appear in a sequel?