Oh, definitely. Boeing has it made for the next decade or two. They've already sold 920 787's, the best selling aircraft upon launch in history. It's what airlines want; a smaller, efficient, 21st century aircraft. Airbus' reaction to it is rather funny; initially, they claimed it was just a copy of the A330, then when they saw everyone buying one, they introduced the A350, which was an A330 with an updated cockpit and wings. However, nobody was impressed, so it was back to the drawing board.
I read an article recently about replacing the 737's and A320's, and while both companies are looking into it, there's no advantage in developing one now until the engine manufacturers can produce new engines significantly more efficient than the current ones.