What are the new features of the HPSE?

Low latency LCD - 15 ms

XT60 battery input

Battery holder 

OSD Voltage display

DVR add-on

RHO Pro lens add- on

New colors

New carry bag

 I noticed that the resolution of the new Headplay SE is lower(1200x600) than that of the Headplay HD(1200x800) that came out before it. Is this a mistake or is it really lower? 

Yes- screen resolution is slightly less, but the latency is much improved. Comparing Headplay HD and SE in HDMI mode with 720P input signal, the lower resolution is hard to notice , but the lower latency is noticeable.