Hi lithfin,
Thanks for giving Spootnik a try! Yes, I initially thought about bringing Basecamp, Highrise and Backpack to-dos together inside OmniFocus. But the desire wasn't strong enough, yet. But I keep it in my mind. Thanks for the request.
There was an announcement of an application which synchronizes AddressBook and Highrise (
http://www.greatascent.com) some time ago. But IMHO it didn't go public.
Best regards,
Lars