Here's a couple of issues we're running into with handshake that I'd love to see improved.
1) The Purchase Order field in handshake should get mapped to its equivalent in dear- the "customer reference" field. Currently the Handshake PO gets put in Notes, and the handshake invoice gets put in "customer reference".
2) Handshake dropship addresses get added to the store's address book in dear. If a customer does 50 dropships a year through handshake, then at the end of the year the customer has 50+ shipping address in DEAR- all of which are useless and distracting except for their actual shipping address. Adding dropship support for orders in Dear would fix this, and also add (I think) needed functionality to Dear's ordering system.