The AOL-Yahoo trial balloon floats again. Bankers are talking, though, possibly, not to Yahoo yet. Some like the potential combo, but our own Matthew Ingram does not. I’m a little more sanguine: AOL has some assets (ad network, Moviefone, growing blog network) as does Yahoo (ad sales force, news, sports, women’s and entertainment content) that could work together, and they both have a lot of email users. But Matthew’s right: they’ve both blown social so far and are clueless about the real-time web. And the effort required to integrate might surpass the benefits of scale, some of which are deceptive (overlapping audiences).