This week's book giveaway is in the OCMJEA forum. We're giving away four copies of OCM Java EE 6 Enterprise Architect Exam Guide and have Paul Allen & Joseph Bambara on-line! See this thread for details.
(Unless you're talking about official S2 support using the tags, in which case jQuery is better, because Dojo support was deprecated. If you're using either framework *directly*, which is my own personal preference, then it's a matter of requirements and preferences.)