In general, I'm strongly against teams moving, because it's just not right to rip out the hearts of the fans like that. I think that any team that just insists on moving should have to do like the Cleveland Browns and leave the name and history behind. Why should banners won in Seattle be hanging in Oklahoma City, or titles won in Minneapolis or Houston be celebrated in Dallas and Nashville? The new fans didn't care about those old days. It was really stupid that the Titans got to wear Oilers throwback jerseys on the AFL 50th anniversary year, instead of the Texans, whose fans actually cared about the Oilers...
Having said all that, I would be OK with one possible move: Move the A's to Sacramento. It's close enough that they could keep their Northern California fanbase. The Giants are more popular in every single ZIP Code, but if the A's became "Sacramento's team" instead of "the Bay Area's second team," they'd probably take over in Sacramento and have a more established fanbase. And they'd be close enough for the random Oakland loyalists to still keep up.
How about moving the Raiders back to Los Angeles? Would you be okay with that move?