Hi kafeeringe,
All of those are nice ideas, and we are already planning to do all of them.
1. Importing contacts is coming very soon, and calendar synchronization will be next. File importing is very important and requested very often, so we will try to stuff it in in a next version.
2. Improving the email module is also one of our main concerns nowadays. The first step will be to make it more stable, fix bugs, etc. Then we will be supporting SSL so that GMail accounts can be checked with OpenGoo (but also to allow for a more secure email transport). IMAP isn'thigh priority but we will try to support it.
3. Yes, this would be nice but it isn't a priority for us for the moment. But if someone is willing to code this for OpenGoo we will gladly include it in the following release.
4. A wiki again is not high priority right now, but we plan to have some sort of wiki in OpenGoo.
Thanks for your feedback!