maybe the problem is the Flash player from those sites?

Nice. I checked the box in the settings for 1080p and it does a fresh reconvert on the video.

This is the exact same file on both youtube and vimeo. Xdcam rendered out as a Blu ray .m2t. 25mbps if I remember right. I think the vimeo looks better. Less artifacts.

YouTube - 1080p video test Sony PMW-EX3 (Treasure Island las vegas)

Oh my god, that video looks jaw-dropping! Both in what has been shot, and the quality of the video online.

Are Vimeos bitrates actually higher for this material? In the past, they limited their bitrates to something like 3 MBits/second to accomodate that average broadband (DSL) line. The cool thing about thie service is that they do allow Plus users to distribute their video with a download link. I just wish they had a checkbox in their player to allow convenient playback of that original file in their player window when you use the Full screen option.

Does Vimeo respect the framerates you sent (i.e. 24P vs 30P) or does it convert to something uniform?

I suggest that you take a look at SmugMug who have been offering 1080p as part of their video hosting package for over a year. Their service for professionals (includes commercial use) costs $150 per year. They don't have any free service & they don't have the self-congratulatory 'community' & awful forum support software of Vimeo but they are damn good at hosting video. They started off hosting photos for professional photographers & have grown their service from there.

I have done a lot of research on the best way to deliver video online at a good price & SmugMug is far & away the best & easiest service that I have found. They offer many advantages over Vimeo e.g. multiple copies of your video are hosted in a variety of resolutions. A problem currently with Vimeo is that you must select either 1080p or 720p for your videos & many people have problems with playback of 1080p due to network issues. You cannot offer a choice.

Here are some of our recent videos hosted on SmugMug Video Hosting - Barkers Videos

Here is a video hosted on SmugMug embedded on a client's site Robert Camuto

Here are some unedited sample videos straight off a Canon 5D Mk II The 1080p bit rate is a little over 7Mbps & the 720p is 3.2Mbps

HD demos - Barkers Videos

Can people share their optimal settings/workflow to publish to Vimeo in 1080p? Which encoding program do you use, which bitrate (target/maximum) and in what file format do you upload the file to Vimeo? I am eager to find out how to achieve the highest quality.

YouTube operate at a loss & have Google's bottomless pockets funding them until they can figure out some way of making money out of their service. Vimeo want to stay in business so must charge what compared to all the other costs of video making is a very small amount.

You need to check that your network is fast enough for 1080p video. I don't know what bit rate Vimeo & Youube use for 1080p but if you check out my videos hosted on SmugMug the 1080p are a bit over 7Mbps & 720p 3.2Mbps HD demos - Barkers Videos

If you can play my videos OK which confirms your network connection is OK then it may be that you need to install the latest version of the Flash Player as SmugMug uses QuickTime when you view from a Mac.

They used to convert all HD video to 25p. (Yes, they converted to 25p that is not a typo). It did terrible things to my Canon 5D Mk II videos making them very twitchy & stuttery. I had to close my account & get a refund. I have heard that nowadays they honour the frame rates when between 24fps & 30fps but higher frame rates get downconverted.

Vimeo has a lot in common with DV Info Net: they're going after quality, not quantity. Just look at the difference not only in the worthiness and watch-ability of Vimeo clips over YouTube, but the class of comments as well. YouTube is a wasteland. Vimeo is actually worth what it costs.

And not to forget - although I am not a paying member - a very clean lay-out and a very easy process to make an account.

Nobody has an answer to this question?

One thing that might help is clicking the "Switch to HTML5 player" link in the lower right of the description area. On my iMac the CPU load of the HTML5 player is less than half of what the Flash player requires (about 9% versus 20-25% at 1080p full screen). The HTML5 video tag lets your browser play the video natively without relying on the Flash plugin, so it's much more efficient. Unfortunately it is only supported by modern web browsers, which is one reason why Vimeo and YouTube don't use it by default, and there is still some dissension among big tech companies about what video formats should be supported.

Even so, it's a huge leap forward for video on the web and I can't wait until it gets widespread support.

Sadly that seems rather unlikely. HTML5 is still only a draft standard. Apple with Safari supports the <video> tag well but Microsoft does not support it all in Internet Explorer. Google Chrome supports HTML5 video (unsurprising as they own YouTube). Both Opera & Firefox only support the HTML5 <video> tag with the open source Ogg video CODEC & not H.264 MPEG video that the other browsers do.

Flash on the Mac is a resource hog & using Quicktime for video playback is vastly superior to using the Flash Player even when the same H.264 MPEG4 video files are being played.