I just noticed that many music videos start playing in HD on youtube without one having to select HD. My clips always start off in 360 resolution and unless the 1080 is specifically selected, it stays in 360. So how do I get YouTube to play in HD right away?
I have never seen a video on youtube default to high definition ever. Bandwidth is the currency of the internet and even in this day and age not everyone has it. I suspect this is the reason for it and I don't see youtube changing it. People browsing through youtube don't want their monthly allowance chewed through without due cause. If they find a video amongst the dross that is worthy of HD they will select it. Also a lot of devices used to view youtube are not HD themselves. I suggest you host it on a site like Vimeo where the users expect a higher quality of content, justifying the bandwidth used.