Rick Warren invited to give Obama's inaugural invocation

Sen. Obama is getting a lot of flack (especially from gay organizations) for asking Rick Warren to say the prayer at the beginning of the inauguration. Warren will get a lot of flack from fundamentalists for being on the platform with Obama. (But flack from fundamentalists isn't necessarily a bad thing, IMO).

There are big differences between the men on issues such as abortion and homosexuality.

What do you think? Is Obama wrong for inviting Warren? Is Warren wrong for accepting the invitation? Or is Obama showing he believes in diversity? Is this an example of what it means for a Christian to be "missional"?