I followed Dreamhack's streams on Justin.tv and it was really an awful experience for me, with several downtime right into the live performances and such.
I do remember someone from the staff coming into the overcrowded channels and expressing their astonishment feelings toward the fact that the chat was actually standing and surviving the load.
Besides that, some phrases they translated into my language are just preposterous, usually it's just better off to do not translate a site at all if you manage to do it in such a way.
I did read all the comments where they've pointed out their many improvements, i hope it will get better and better since a platform like that has great potential.
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