Date is 10/11/2015.
Surface 2 (RT, not pro) - all updates applied (including optional updates).
The amazon video issue is fixed for me as of this evening - I went into the IE settings and turned off "Do not track" under "privacy". The updates alone did not fix the issue - but for some reason this extra tweak did.
Under the settings on the Amazon site I have checked the "silverlight" option as the preferred player.
working now very well.
XFINITY on demand seems to be working pretty well too, but the ads are often black (w sound).
HBO GO still stutters and is un-watchable.