At some point recently visual editing support seems to have been added for the Mac.
It looks like a bug was introduced at the same time. If I edit a page, and put multiple P elements inside a TD inside a TR inside a TABLE, then after saving it, the paragraph tags have been lost, and the text has all merged into a single paragraph.
I had two tables in the same page, and there seemed to be some circumstances in which paragraphs would be retained in one of the tables but not the other.
I tried using the visual editor, but it has the same problem. As I'm on a Mac (using Safari), I don't know if this is a Mac issue, or possibly even a Safari issue.
Finally, any chance of a config option so I can specify that I want the Code editor view as the default, not Visual. That would save me a mouse click for every post :-)