The Beta will be released soon, within the next week or so.
Read this announcement, contains some info about the beta as well as new changes.
My configuration table is just in a simple format, config_name, and config_value (just like the phpbb configuration table). As for the other tables, there's a table for weblogs, table for entries, and a table for replies. Each with a foreign key linking them. You probably won't need to
"mod my mod". If you want to include part of the system, you can just create a blog for that user (it's one blog per user), and then in your portal you can pull out the data for just that blog (i.e., get entries with a specific weblog_id). You could also add contributors to it too. That would most certainly take care of most of the work you need for the blog module.