After a long night's work, the website calendar now automatically feeds off of Blizzard's Armory calendar. It will fetch updates every 3 hours, and add / update events as required. Stale events (those that have already started) will be left alone for historical purposes.
Included in the raid events are lists of people who have signed up, been confirmed, are stand by, or are tentative for the raid, as of the most recent feed update. The in-game calendar will always be more current, but the website calendar shouldn't be lagging too far behind, so you can check raid info from work. As the enrollment lists change in game, they will change on the website as of the next update.
Also, for IE8 users, the list of upcoming events on the home page is a widget, so you can dock it to your widget bar in IE and check for upcoming events without even coming to the guild website! (Not that we don't want you to come to the guild website...)
(Note that if an event's name changes in game, it will show up on the website as a different event alongside the original event, because Blizzard's event ID for each event actually changes each time I fetch the data, which is a bug that has caused me some frustration before I realized what was going on. I now index the events based on start time and event name, instead of Blizzard's event ID.)
The full website calendar can be found here, and a list of the next 10 events from the calendar is shown on the home page.