Tags are just words, not multiple words, this is how YouTube parse tags.
 i  do understand that tags are just words but in many cases combine of  words should be tags, if you just give a minute and check my sites tags,  you will see a ling underlined links in my all video tags, and that  looks like spam for search engine which can't be searched, youtube is  not using only single word as tags, (check this video tags:  
YouTube - ‪Lil Wayne - How to Love [New Music 2011]‬‏)  and when you go the the one of the underlined tag, you will see a  searchable link and it will search the exact or related videos from the  site. in my case it is giving me all videos starting from the beginning  video id 1 or so..., i had fixed this problem in earlier version through  you though..comma should separate the tag and between two words there  shoud be hyphens so it would be seo friendly tags i think.
We will be releasing a patch for this shortly.
-i am waiting for the patch so it will be looking well paragraphed, specially for lyrics part.
There  is no change in SEO side, only change done is returning 404 page when  there is no page, before 2.8, it did not return 404 error for non  existent pages.
- i acknowledged that , it is great, if the video title (i think from  htaccess file) comes first and the site name after that, would be better  for ranking as i have tested this method in WordPress and it works fine  with search engines. if you check (site:
www.clonevideos.com) in Google  all of my link listed by Google are mostly with the site name first. i  have no idea if it can be done??? 
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