Olympus OM-D E-M5 and Star-Lapse or Astro Photography

I used to be an Oly junkie in the 70's (I still have my OM1 and OM4 for the rare times I use film on my Celestron C8), but have been through the Nikon and Canon rack too. Currently, I am into Spherical and Time Lapse photography mainly using a set of three Canon 40D's.

I was wondering if anyone has done any Milky Way, star-lapse, or even daytime time-lapse yet. I've done some searches, but no samples come up. The high ISO samples I've seen has the Olympus OM-D E-M5 close to the 5DmkIII in JPG and close enough (for me) in RAW.

I would love to know how this camera compares to the industry standard for night-time star work, the Canon 5DmkII (or mkIII). At the current cost, I could nearly buy 3 Olympus OM-D E-M5's (with kit lenses) for the price of one 5DmkIII body.

Any feedback is welcome...