Linking to MLBTR because the original link (http://networkedblogs.com/tOzVv) is to a spanish language site.
Per MLBTR's translation, the offer is in the vicinity (and likely a little below) $40M over 6 years, so less than $7M per season. It seems to me that creates the opportunity for the Cubs to come in on a shorter deal at higher value per season - i.e., not the 6x60 deal people were worried about, but maybe 4 years and $8 - $9M per season. The overall value will compare favorably with the Marlins offer, but give Cespedes the promise of a new free agent deal sooner than he'd get from Miami. If he plays well, the deal they offered would quickly look very unfair to the player, and he wouldn't hit the market again until 32.