After Apple formally announces a new version of iPhone OS and gotten it into the hands of developers, they tend to follow up with minor releases every 2 weeks or so. With iPhone OS 4 having been announced 12 days ago, it seemed like a new Beta couldn’t be far off — and sure enough, iPhone OS 4 Beta 2 just shipped.

So what’s new?

We haven’t gotten wind of any exciting new user-facing features yet, but we’re hearing about a few new tricks it’s packing for all the developer folks to fiddle with.

Amongst these is EventKit, an API which lets applications plug events into your Calendars (like Facebook automatically throwing in all of your friend’s birthdays), and Quick Look, which seems to provide apps with a means to allow for users to preview certain file types (iWork, Office docs, RTF, PDF, images, and CSV files) without launching into another app. The latter has to be plugged into apps manually, so don’t expect it to work universally right off the bat.

We’ll let you know if we hear about anything else.