To be a great development team, your team needs to devote time to continuous learning. A team that doesn't regularly encourage its members to take time to learn new skills and keep up with emerging technologies is bound to fall behind in their skill sets and will often not identify the best solution for a given problem. I've worked with teams that encouraged continuous learning and teams that left no time for it and I can tell you with certainty that the teams that encourage continuous learning are the best development teams.
Continuous learning can take on many formats. Some suggested ideas for continuous learning include weekly knowledge sharing sessions, encourage developers to attend developer conferences, have your team participate in and present for local technology user groups, start a book discussion group in which your team discusses a technical book each week. Be sure not to focus your learning sessions exclusively on the technologies that your team is currently using. Allow developers to expand their horizons and investigate emerging technologies and then share those with the team. While these may not have an immediate use, they keep your team aware of whats available and always ready to find the best solution to problems at hand.