No markup tags should be necessary to start a new paragraph.
We encourage engine developers that have already implemented the Creole 0.3 style (blog-style) line breaks not to throw away their implementation, but to add an option so that administrators can choose in which mode to run their installation. This way we hope to gain more experience with blog-style line breaks. In a blog-style line break mode, the forced line break syntax must be supported, so that line breaks will properly migrate when people copy text from a wiki with forced line break characters. More details
More details: List Of Line Break Markup