I've been waiting for Kelly or one of the other coaches to jump in here, but I can't resist. First, a disclaimer: I'm not a coach, but I play one around my office.
I consider myself fairly black belt about GTD. Here's what I do:
I keep my calendar and all my action and project lists in Outlook 2007, with the GTD Outlook Add-in, on my laptop. The first thing I do when I get in in the morning is open up Outlook, which automatically opens to show my calendar and, on the right side, all my next action and project lists. I scan my calendar (in week view) as a reminder of any appointments that day, as well as any all-day events or information I put on that day. If there was something I know had to be done that day (and would die or get me in trouble if it wasn't), it's on my calendar that day as an all-day event.
After scanning my calendar, I then look at my action lists for the context(s) I'm in: @Office, @Computer, etc. I also scan @Waiting For to see if there's anyone I need to nudge. Only then do I process emails. I stick strictly to the two-minute rule as I do so. In fact, I generally spend less than two minutes per email -- I get bunches, and I'm generally able to get them into the right places pretty quickly.
Finally, I start "doing." You all know the drill. And you also know there's no mathematical formula for deciding which of the many next actions to do first, then second, then . . . Keep scanning your lists. If you've done the thinking up front, you don't need to re-think your next items to decide which ones to do. Now you're just working off of punchlists.
The problem with a daily to-do list is that at any minute you can get something new that makes that list worthless. Your daily to-do list may hold pre-defined work, but that's only one of the three categories of things you need to be doing. Sometimes the ad hoc stuff that shows up requires a complete reshuffling of your day and renders your daily to-do list obsolete. I also have a real allergy to writing and re-writing the same stuff on a daily to-do list.
I also do a weekly review (weekly, believe it or not), which is key to keeping things current. I also regularly take a few minutes each day just to see what's coming up on my calendar and look at my project list to see if something new needs to be add to my next action list. Just a quick scan, not a complete review.
Of course, your mileage my vary, but after years of working with GTD and testing ways to do things, I have discovered that -- surprise -- the system as David describes it works amazingly well for me.
Randy