Our reader Willy discovered a nice addition on the E-M1 brochure. It now shows the camera with the new 40-150mm PRO zoom. I attached the image here on top while the new brochure can be found here: http://www.getolympus.com/us/en/em1_brochure
Now you can get a nice idea of the camera-lens dimension :) And here is the description from the brochure:
M.Zuiko 40-150mm f2.8 PRO 80-300mm (35mm camera equivalent) Available in 2014
Incorporating the same powerful optical and digital technologies developed for the top-of-the-line Zuiko Digital lenses, M.Zuiko PRO series lenses are designed to bring the highest level of professional imaging performance to our line of compact Micro Four Thirds system cameras. The second model in this series is a telephoto zoom lens with 35mm camera-equivalent zoom range from 80mm to 300mm. Built tough to stand up to the harsh demands of professional use, this high-grade lens boasts optical performance with f2.8 brightness throughout the zoom range and a durable dust-/splash-proof structure. Together with the 12-40mm f2.8 PRO standard zoom lens, this new lens enables the PRO series to cover the widest possible range of photographic requirements.
Note: There is also a 1.4 times teleconverter patent along the 40-150mm f/2.8 patent discovered by Egami.