I ran across an informative article on Mail Consolidation here at DMNews:
It is important to understand what each of the different “Co” programs that are all the rage right now –
These definitions are from the USPS Quick Service Guide 800 Glossary of Postal Terms and Abbreviations found in the Domestic Mail Manual:
commingle To integrate dissimilar mail (such as subscriber and nonsubscriber copies or machinable and irregular parcels) into the same mailing.
These definitions are my own take on the processes listed:
comailing, as opposed to copalletization, combines individual pieces of mail, rather than bundles, in order to create bundles with a higher presort threshold, allowing pieces to be married up with other pieces going to the same zip code, boosting qualification levels to get deeper piece discounts.
cobinding occurs during the actual manufacturing process, and allows mail of like trim sizes and comparable page make-ups for different finished products to be produced and sorted as a single mail stream.
For more in depth comparisons and analysis of these processes, just run a Google search by the process you are interested in, there are many more detailed resources and specific company services listed for reference.