Nite Flyer,
No i dont believe what they told us depended on experience, as i have enough experience for the 777 too. Durng the interview lunch chat they joked about how 'mad' people were waiting for the 777. I know how you feel as the 777 is what i wanted. But i dont believe its an option anymore.
As the others have said dont hold out. Seniority is key. If they take you on 777 in Oct lets say and your on the bottom and they dont hire anyone externally for years, for the 777, you will remain at the bottom of seniority on the 777 fleet. Even though you've been flying it for longer, you will be junior to them as they have more company time. Just take what they give you!