Keeping notes locally is good, however local machine might not work sometimes, thus it still nees to export the Obsidian files time to time…
So the question is:
Thanks.
ignore the question #1… I forgot that I create the vault myself.
the feedback on question #2 is still welcome
Sync is planned, and high priority: https://trello.com/b/Psqfqp7I/obsidian-roadmap
Does anyone know how to export to pdf?
Your best bet is to use pandoc to convert the markdown files.
New to obsidian and joined the forum to comment that being able to export an individual note to pdf in the obsidian menu would be super handy. So I second this feature request.
Since the files are all exposed to your system, you can go directly there and convert anything to PDF. Personally, I would prefer the team focusses on really unique Obsidian features than try and replicate features we can already do ourselves since the files are ours.
And that’s a valid point - desired features that don’t have a current workaround should take precedence. Like I said, I’m new to Obsidian, came by way of Roam, and I’m really looking forward to seeing how Obsidian develops over the next year or so and being along for the ride. I know there are a lot of cool features coming. One day, though, I hope not to have to use a third party software to export notes.
Oh yes, absolutely - the more the app has features the better, in the long run. 
It would be nice though if it were incorporated into Obsidian.
Regarding your original question, Obsidian Sync is now released, and you can roll our own sync too (either cloud based or self hosted).
So unless you mean standard Markdown export, I’ll archive this feature request? @dracohu