You are correct that iCal to-do lists aren't sync'd to the iPhone yet.
As far as I know, the only sort of iPhone integration for OmniFocus is a script (described in
this thread) that converts your OmniFocus actions lists into a set of HTML pages (or maybe it's just one page) that you can then sync to the iPhone. It's a clever hack, but it's mainly just giving you a read-only view of the list.
Hopefully, with the arrival of an official iPhone SDK in February, OmniGroup will consider developing some sort of iPhone application that allows you to manage your tasks directly on the phone, and sync back and forth, etc.