Hey there !
Historicaly, they were always two types of YouTube partnership :
- Official YT partner, sign a contract with Google
- Partner with an external network who signed themselves with Google
Since less than a year, YouTube split it's original partner program into two tiers
- First tier is accessible to a wide variety of content creators, it allows you to monetize videos and use the schedualed uploader. You can also stream live shows using Google Hangouts on your YouTube channel.
- Second tier is the "legacy" youtube partnership, where you can upload your own thumbnails, banner etc...
According to your post , you seem to have been accepted in the first tier of YT Partner program, yay !