If you get on there's a nice button at spawn you can test.
It's true that builders can't make or edit command blocks for obvious reasons but they can be triggered by builders.
As for my hopes in command blocks... I hope they get some (small) use in the PC gamer server. Nothing huge. Maybe a weather control (to cut down on some lag) and maybe some other small things (PvP maybe). I'm not pushing for this but It may cut down on some smaller plug-ins that need updated every so often.
Not sure which plugin that will cut down on, command block still needs to trigger the command the plugin provide.
Weather control: Maybe, weather is off at all time on Creative map though
Time control: If so creative only or /ptime only
The reset will not happen before 1.5 is out, and 1.5 might be a game changer when it comes to plugins and features of the server, we might move away from bukkit thus make our updates faster.