The long-awaited Microsoft-Yahoo search hookup may happen soon, according to a report attributed to ThinkEquity analyst William Morrison.

We've heard that a few times before, and the latest take was deflated by Eric Savitz at Barron's, who was told by the analyst that the initial report was inaccurate.

A Microsoft spokesman said the company will not comment on the latest speculation.

Who knows what's going on, but the timing does seem logical.

24/7 Wall Street said it heard this from Morrison:

Sources beyond ThinkEquity speculate that under the terms of the arrangement, Yahoo! will be paid $3 billion upfront and will get 110% of the revenue that its searches provide after traffic acquisition costs in each of the first two years. In the third year, that figure would go to 90%.

The report noted this would give Microsoft 30 perent of the U.S. search market and keep Bing's momentum going, after its initial launch bump.

Microsoft has $3.75 billion on tap from a debt offering in May, and Yahoo's new boss has said she's open to a deal if there's enough money on the table.

Now would be the time for Microsoft to close any such deal.

It's going to report fiscal year-end earnings next week, and hold its annual financial analyst meeting the week after that in Redmond. Bing's outlook and the status of the on-again, off-again Yahoo talks will be among the questions Wall Street types will have for Ballmer & Co.