Actually, it may not be what you’re looking for: it is planned to offer a “log” field that allows you to create a set of fields that will make up a running log. It’s for applications such as a volunteer timesheet, an attendance log, a list of items in the user’s collection, that sort of thing. Anything that needs a list of items that can be added to, edited, and so forth. Each item will be a set of fields such as name, date, etc.
So, it’s not a fully relational database, it’s more like a database within a database, with a single fixed point of relation between the two.
The timeline is probably on the order of 2-3 months, it’s still in the planning stages.