There's so much new stuff in Exchange 2007, that it's easy to forget just how useful some of it is... like the calendaring improvements both in the UI of Outlook and OWA, but in some server-side cleverness too.

In Exchange 2003 and earlier, when someone sends you a meeting request, it will just sit in your Inbox until Outlook picks it up and does something with it (depending on how you have Outlook configured). One standard behaviour would be for it to take meeting requests and stick them in your calendar as tentative appointments which you've yet to respond to. Outlook does need to be running, however...

This could mean that if you're on holiday, people might be sending you meeting requests which conflict, but your free/busy time might look free because Outlook isn't running. Exchange 2007 now does the tentative booking of time on behalf of the mailbox, as well as taking care of other meeting hygiene features - like removing out-of-date meeting requests when the organiser sends a change (solving another pain if you've been away for a while, and come back to loads of meeting requests which are out of date). This is part of what the "Calendar Attendant" does - more calendaring stuff can be found on a description of the collection of services referred to as the "Calendar Concierge".

Now, I'm on a lot of internal distribution lists which I filter from my inbox into subfolders using server side rules. In the past, I'd sometimes missed conference calls etc where invites had been sent to the DL, but had been moved into my subfolders before Outlook had a chance to shove the tentative meeting in the calendar. Now, with Exchange doing both acts, anything sent to me directly or indirectly will get put in the calendar. Nice!

Well, there is one downside - in a multinational company, there are meetings and conference calls going on at all hours of the day and night... and invites might be sent to DLs to drum up interest in attending. It's easy to forget to switch off your phone or PDA from reminding you about the out of hours meetings, if you're not in the habit of deleting/declining the requests...

Sometimes, it's the seemingly little improvements that make applications so much more usable - and yet don't get the same degree of attention. The Calendar Concierge is definitely one of them!