Alan-
One thing I didn't see suggested yet was if you're going to push the update, you may want to cache it first. The Office updates can be rather large (especially since they're finally combo updates now...Adobe, take a hint). Depending on how many you have to deploy, you could take your installed base, divide by 5 and cache that number per day over a work week. (Maybe split it up by department/network/building etc.) Then, set a policy to install all cached updates when people log in Monday morning. They'll all be taking their time on a Monday to get up and running anyway and if the package is cached, it won't take all that long.
I saw someone else post that for non-critical updates, they let people pull them down with Self Service - a good idea if your environment allows that. You may want to consider implementing a patch schedule. We're in the middle of deploying SCCM and Casper enterprise-wide and the patch schedule will be huge. I'm actually following Microsoft's <gasp> schedule - mainly because they have one! (Apple, take a hint.) On Patch Tuesday, any updates in our Software Update Server that have accumulated since the last Patch Tuesday are released (assuming they've been vetted and there aren't any show stoppers). Users have two weeks to self-install them with the usual Software Update. After those two weeks, I force install. For Adobe and Microsoft patches, I try and deploy them as in-frequently as possible, in-line with Patch Tuesday if possible, though that's not always do-able. Luckily, those don't typically require a reboot so they're less intrusive.
Consider it... Users appreciate knowing when the schedule is and that you're not going to interrupt them with bothersome updates if you aren't scheduled to.
j
