I don't have pinboard, but i believe some of the differences are:

It gives screenshots, It saves content for later and it's an official Opera extension (pinboard doesn't have an official one).

Edit: Raindrop.io also let's you save the content of video. That's a pretty handy feature pinboard and dragdis don't have. I don't know of anyone else that has it.

Will you be supporting the new Opera 15+ browsers?

Opera actually is supported. You just need "install chrome extensions" extension and then you can use it fully :)

i'd really like an app for this for my phone. i love the music and visuals.

i'm guessing you could use a shoutcast stream with an auto dj in the cloud or possibly mixlr.

edit: since you want voting, i think mixlr.com is what you want, it's $10 per month or free. i know grooveshark has a radio station thing now too.

any plans for an opera or chrome extension?