I don't know that the cubs would even have to send the Yankees cash. They might do it outright. Soriano is worth more to the Yanks, he'd be a solid run producer in that line up. The Yankees are probably willing to eat 10+ mill a year for two years to send him to the Pirates. That's more than they would pay for the last year of Soriano's deal (18 million).
There is absolutely no way in H the Yankees would do a Burnett for Sori swap outright. Sori is due 54 million through 2014 and Burnett is due 34 million through next year. So not only are they losing the 20 million throughout the duration of the contracts, but they would be losing 18 million off the books in 2014 to use on FA's. Sori cannot field, he strikes out too much, and he no longer can steal bases. He is not worth half of what he is due over the next three years. If the Cubs got offered this deal they should take it immediately and than go straight to the casino. They can find a better DH that is a FA on waivers for a one year deal that will come off the books next year. AND move Burnett for prospects.