all119,
I have been told that in the future, 787 pilots will likely be sourced from the A320 fleet (obviously subject to change on a whim). So, even though you may get assigned the A320 initially, you could end up in a 787 a few years down the line...
Stay positive, smile a lot, don't stray from expectations and kiss some a$$ and it just might happen!
I've heard eventual A380 and A350 seats will be sourced from the A330/340. I guess the 777 pilots are expected to stay in their fleet - who knows???