We first heard about the existence of the Acer M310 Windows Phone last week, but literally no information was given besides the fact that two test units were discovered on a developer's traffic sheet. How about a few more shreds of meat to chew on? According to WindowsPhoneNZ, the Mango device was sighted at TechEd New Zealand with HDMI-out support. We may be seeing this feature across a large variety of Windows Phones coming out this fall, as the HTC Eternity has been rumored to include video output via HDMI as well. The observer claims the M310 has a "black shiny look" and "bevelled edges," has a similar appearance to the Acer W4 (shown in the above image), and includes DLNA support over WiFi. The handset was also seen snuggling up to Asus' entry into the Windows Phone market, which was said to have a matte black finish and may have a front-facing camera. Certainly, if these factoids are correct, this fall's Mango lineup looks to be laden with all kinds of hidden gems we haven't seen on Microsoft's OS yet.