Just had a quick look at what it claims to do and it took me a bit to realise it's related to the fb2k plug-in that I'd seen a while back when starting on my in_url + youtube-dl solution (which doesn't support vimeo or dailymotion but could be since youtube-dl claims to support them).
Without actually trying it out, I'm not too sure what is needed to get it working with Winamp's in_dshow (assuming it's not something that in_dshow is blocking or just isn't detecting the urls correctly). Though I'd more prefer to focusing on my existing option as that works with the existing Winamp plug-ins, etc without having to really mess around with lots of settings.
Not sure on the online services aspect as those views aren't that helpful unless it's implemented with a solution that makes use of the hooks that Winamp provides instead of just slapping a web page in and hoping that opening links will work correctly into the current Winamp (which is not always guaranteed).
There is a way to make such videos play without the video aspect by just generically disabling Winamp's video support but finer control would make more sense. Would have to check the youtube-dl responses as I think audio-only options are also available from that (though it depends on the service being used).
Will have to sort out some time to look into this a bit more to see if it's worth it for the playback aspects. Though as I've already got a solution for doing the same base aspects without the need for extra dshow filters I'm not as enthused as I might have been a year ago due to in_url now existing.
-dro