I don't have anyway of showing you right now but all of my HTPC streaming content which is recorded at 1080p plays just fine on my phone.
It may have been recorded at 1080p, but it's being converted by your computer to something else to be able to stream and play on your phone.
Broadcom has had a chip that will do 1080p (on mobile phones) for a year now. Pretty sure some other manufacturers as well, but we haven't seen them in a mobile phone yet.
1080p resolution is 1920x1080. No phone's screen has that resolution yet (and really on a screen this small, you don't need it) so nobody is viewing true 1080p on their phone. What you are seeing if you are playing a file like this is something that has been downconverted to the resolution of your phone's screen.


