Here's my best attempt at answering your questions:
1. If you're already working with data in OJS 2.2.0, I'd say continue and upgrade to 2.2.1 when it comes out. Usually this is a straightforward process, and almost certainly easier than waiting and duplicating your effort into a fresh OJS install. We're hoping to have 2.2.1 released within a few weeks.
2. The next release is a maintenance release, and mostly incorporates bugfixes and smaller feature enhancements (although quite a number of them). At the moment, OJS handles article files as they are uploaded -- ie. it merely displays them directly to the user in the same way they are provided by the editor. Most journals publish their article galleys in HTML and/or PDF formats for obvious reasons, so any features related to statistical formulae, LaTeX, or MS-Word will have to be handled before the final article galley is uploaded to OJS.
A footnote on the second point: we are working on another application, Lemon8-XML
, to handle more complex article file formats and requirements, but at this time it's still under heavy development, and focuses on XML rather than LaTeX. We may move in that direction in the future, but it's still a ways off.
Hope this helps,