Thanks! The software scales up to that stuff. There's a bunch of complicated stuff transcribed on Soundslice. Here's an arpeggio exercise in the style of Satriani et al: http://www.soundslice.com/tabs/4976/electric-guitar-solo-cra...

The slow-down feature helps. :)

I chose tabs to start because (1) it's easier to implement than standard notation, (2) most guitarists use tab instead of notation, and (3) classic tab really needs to be brought into the 21st century.

With that said, I'm working on a standard notation version now, and it's going to be amazing. It's a surprisingly tricky technical challenge to render sheet music in the browser -- there are centuries' worth of special cases!

Did you consider/play with Lilypond at all?

Yes, definitely looked into Lilypond. It produces beautiful sheet music, but I can't use it because (1) it's GPL and I intend to license the technology, (2) I'm generating the notation client-side (for responsive design) and (3) I need the ability to highlight certain notes in real time to show the user which notes are being played.