I'm reading the support for Lieberman from Obama a little differently than others seem to.  The key quote to me is:

"President-elect Obama looks forward to working with anyone to move the country forward," Cutter continued. "We'd be happy to have Sen. Lieberman caucus with the Democrats. We don't hold any grudges."

What this refers to is one of the things that Obama seems to be especially skilled at:  he can find common ground on specific issues with people who are not usually in alignment with his views.  Since Lieberman is reasonably liberal on a number of issues, I think Obama sees multiple opportunities to pull him in to an alliance and build a filibuster-proof majority for those issues.
What this statement does not say is that Lieberman has President-elect Obama's unconditional support.  I think the it leaves plenty of room for the Democratic Senate leadership to move Lieberman to a committee chairmanship that fits his "Democratic" side, and place a more appropriate person as chair of the Homeland Security commitee.