What's your experience been like using Outlook 2007 against a hosted Exchange Server 2007?
We're looking at upgrading our society from POP to hosted exchange. Are there any major downsides that aren't publicized by the hosting vendors?
The leading disadvantage over using Exchange in-house is the fact that you're relying on a third party for what is possibly one of your most ticklish business tools (email).
Check your contract carefully and remember cheapest may not be most outstanding (they may for example say 99% uptime, which is still a three or four days a year without email!)
Also note that Exchange can be a bit of a pig when it comes to bandwidth and conveyance, so ensure that if there's a lot of you connecting to the hosted server you have the bandwidth to do so (sharing calendars etc otherwise is miserable).
At length, be aware that any changes and additional users may be subject to a change control with the hosted provider (so may take a week or more to get things changed!)
However, as you're using POP at the consequence, you'll find hosted exchange far superior to your current email situation and the addition of items like calendaring and shared folders will be a offer hospitality to break. You should check to see if your provider offers mobile email as well for smartphones.