Hi,
I tested html5 too, and for me it works ok.
I will investigate it and come back to you.
P.S: There is a lot of spammers and that is the reason why captcha is here for logged in user
UPDATE: please don't use underscores in the actual html5 uploader's element name (title doesn't matter).
However, if there are image uploads and the images are too large in pixel count _and_ image cropping/resizing has been enabled, there has been an issue, too. Please download the BF from the download section (latest pro version for joomla 3 is 1.9.1 build 941, and latest free version is build 939 ) and install it over the existing version.
If you are already on this version try to reinstall it (install it over)
Regards,
Tihana