Your project will be graded on my perception of your level of understanding of the concepts we discuss in class and your level of effort in trying to incorporate those into your project system. This grade will also incorporate a social component (i.e. I will get feedback, either formally or informally, from other group members on your level of contribution to the project).
You attendance and participation will be graded on my perception of your engagement in and willingness to contribute to the class learning environment. Things that help my perception of this include doing your reading, making thoughtful comments/asking questions in class, email discussions, contributing to the wiki, etc.
Your presentation grades will be based on how well-organized your presentation is, your use of time, the quality of your visuals (do they effectively communicate), your oral presentation (polish, etc.), your addressing of questions, and, of course, the content of your presentation.
The bottom line is, if you are actively engaged in the class and are working hard to contribute to the success of your group project, you will do very well in the class. If you are not, you will do less well.