"I don't think adding "hd" to livestreams.com, carries any value above registration fee"
There are plenty of websites that offer live streamings at different levels of quality . HD indicates the kind of quality one expects to get: high definition live streams.
I believe Hd has some value. Just check namebio to see yourself. I pulled some sample domain names starting with 'hd'.
"it's also vague, as you don't know what kind of streams are available"
What about livestream.com? it's vague too but was sold at 100,000 USD (2009-04-23). When I first bought the name, I intended to make website that provides various streamings: sports, gamings, youtube, facebook lives.... My plan was a general streaming sites. But I've been too busy for that.