I wish wish wish that I could recommend Google Calendar as a startup tool with no reservations. I can't though and I we are going to have to switch away from it.
I think that it's great when you're two guys (or gals) in a garage but it really breaks down as your organization grows.
- Great UI - easy to create new events
- Great UI - easy to move events
- Great UI - easy to change how long an event will be
- Web based so you can see it anywhere
Doesn't handle personal vs.work accounts
It's a really big pain to use if you have multiple email accounts. Say an account for work and a personal account. If your Google account is hooked up to your personal account (like mine) and then you start getting calendar invites to your work account the integration is unworkable
Sharing model doesn't scale with your organization
The way you share things in Google Calendar (if you don't want to share it with whole the world) is you have add people individually to give them permission to see your calendar. This is fine when you have two people, you go in and you give the other person permission to see it. When you have 10 people the model really begins to break down.
Each new person who joins the company needs to share their calendar to every other person in the company AND every existing person needs to share their calendar with the new person. This is non-trivial and people balk.
Lack of Outlook integration
This one is truly killer. Sales people love love love their Outlook client. You have to pry it away from their cold dead fingers. They complain constantly about how the integration doesn't work. Ultimately this is the tree that broke the camel's back.
If Google can fix these problems (which seem relatively solvable) they'd have a killer tool that I'd certainly be willing to pay money for.
In the mean time I think we're going to look at a hosted solution for Exchange.