It plays music for me.

Oh, I see, I've got it to work now. I was just clicking "add to playlist" and nothing was happening, but if you click on the name of the song it starts playing.

In which case, very impressive. I'm particularly impressed that it even finds mashups, and the interface (apart from the difficulty I had with getting it to play) is very nice.

I hope you've thought through the legal issues. It could really use a FAQ with answers to questions like "So where the hell is all this music coming from?"

I missed this too - I think putting a little play arrow next to the "+" is in order.

Other than that, I love it.

Further comment (because I've continued to play with it, because I think it's awesome):

I've found a couple of tracks where the time (in green on the right as it plays) was given as "NaN:NaN". That's probably not a desired behaviour. (fwiw the track was "Thunderbirds Are Coming Out" by TISM)

I'm guessing you have javascript turned off? Otherwise the songs should just play instantly.

Why, oh why does such a site require Javascript?!

edit: I'm not against requiring Javascript for those parts of your website that absolutely, positively require it, but everything that can work without JS should gracefully degrade.

I didn't downmod, but I don't agree that everything that can work without JS should gracefully degrade. That seems like a lot of extra work to support a miniscule segment of fussy purists.

What am I not getting?

Well, JS is turing-complete and that's both a blessing and a curse. It's a blessing because you can do "anything", but it's a curse because unconstrained code is opaque. It's very hard to do stuff like extracting the semantics (what you meant to express when you wrote the code) out of JS and doing things like transformations without an unreasonable amount of work.

I think it's better to express as much as you can in a more "constrained" language like HTML or CSS because it's more like data than code, so it offers less opportunities to make a big mess of spaghetti code and having obscure interactions in the code. It's easier to reason about. HTML and CSS, being declarative, are much easier and cleaner to deal with than JS (it's more WYSIWYG).

So I guess what I'm saying is, coding in a style that avoids JS as much as possible is beneficial, and that style facilitates graceful degradation. Conversely, keeping an eye on graceful degradation will facilitate a better style.

Thanks for explaining. Now I'm sure I disagree. :)

I'm partly kidding. I might use that design style under some circumstances. I disagree that it's the right way to do things. There are many ways to do things. I think people want a "right" way because they want to feel like they've got stuff figured out. (This is especially common in our world because software is complex and there's a lot of uncertainty around how to do it well.)

As it happens, the app I'm currently working on is as far away from this design style as you can get. We do almost everything in JS, even things that could easily be done in HTML and CSS. Our way of carving things up relies heavily on expressing everything in a single language, and the Turing-completeness of said language is an advantage not a disadvantage. It's a solution I'm fond of because it neatly combines high-level abstraction at the source level with some stringent performance requirements in the browser. It will also be fun to watch the purists turn green when they see it.

Edit: we do almost everything in generated JS. Might be relevant.

I tried it without JS for seo reasons but the background flash player just wouldn't work. I had no other option. Plus jQuery is just too awesome not to use ;) I love it.

Isn't jQuery advocating and encouraging "non-intrusive" Javascript and graceful degradation?

JS support is required for the flash auto-play on IE due to some rediculous patent dispute.

Didn't automatically play for me-- I was able to add songs, but had to right click to show my playlist and left click to get started. FF3/Win.