I went to the US page for E450 series earlier today already and yes, the latest firmware available there was the 1011.13 issued on 3.06.2012.
Since the major difference between these european and US models is the TV tuner only I think I am pretty sure they fixed there something not related to the tuner only in the latest firmware, so it should be coming to US soon as well. Can be months though judging by the previous updates.
When I was using the Estonian Samsung site earlier today where I browsed to my product, then to 'Support' section -> firmware, there was still the 11 months old firmware there, so I found the new firmware through the main support web address I was directed to (this one is in Estonian) -
http://www.samsung.com/ee/support/download/supportDownloadMain.do
When going to the local Samsung's page for my product page again now few minutes back there was this new two days old firmware there too on that page when browsing to support section. So this firmware is that new they are updating the links on the websites still.
There was an update to the european E450 models in the 4th of October 2012 as well (I remember downloading it, but not applying). So no idea about when they bring the upgrade to the US models and no idea what it would fix or make better.
The newest downloads for my model for example are here (firmware is found in the left column called 'Püsivara')-
http://www.samsung.com/ee/support/model/PS43E450A1WXBT-downloads
In English, this is UK's download for PS51E450A1W (works for all european plasma E450 - E530 models and LCD 4 series and up to EH/ES 5300 LED's) -
http://www.samsung.com/uk/support/model/PS51E450A1WXXU-downloads
There is no description as to what this latest upgrade does to the TV. :/ I am hoping some of the PSxxE450 owners finds this out and posts it here too!! What this upgrade does can be found out in some extent from all the E4 series, ES 5300/EH5300 and below series owners too, LCD, LED or Plasma. You can contact them to find out if the new fix changes the video player behaviour to them.
It won't show any new firmware for your model indeed. I tried it with
samsung.com/us/support
It is a good idea to contact the Samsung I think. I hope they answer you. Then the upgades might happen quicker and you can find out more info on the video player capabilities when asking them.