Thanks to Sitecore we have license for the MVPs, but what can I do with it? Is it allowed to share it with a direct colleague to do some research? Or can I use it for a client presentation? Is there any place where I can find the rules around that MVP license?
You can use the Sitecore Platform license only for personal purposes: installing Early Access software, develop an open source module, testing and learning new features and this also includes running your own blog or hosting an open source project.
You cannot give it to anyone else, you cannot run any client solution with it, you should not use it to demo/sell Sitecore; for any of these activities you will need a partner license or a demo license.
You can use the Development Collection tools license also for production purposes.