I would reproduce the actual text from the EULA for a new on-line free to play game that I recently saw, but due to the embarrassing terms and what could actually be a copyright violation by republishing it, I will summarize what they expect you to agree to. This is only a small summary of one section of the agreement
Amendments
The company may change our agreement with you or modify the rules of conduct at any time without notifying you about this. However, we will post the new terms on our web site. These changes will take effect immediately after our posting them. Your use of “Game-service” after the posting date of these terms constitutes you agreeing to the new terms. You agree to check out the current agreement terms and the rules of conduct periodically so you remain informed as we will modify terms and conduct from time to time as we will not notify you of any change.
This is actually a genius solution. Most people don’t bother to read the end user license agreement when installing software. The odds of them constantly monitoring an Internet site and reading the complete EULA looking for changes are almost zero.