Another overlap in search I've noticed recently is 'People Search'. 9 times out of 10 this leads me straight to LinkedIn. I imagine the overlap in this area will also have a negative effect on Google's market share.
Pud - First of all congratulations. 404, 772 users is serious business!
You already have a nice platform for musicians. How about connecting those musicians to help them form bands? As a drummer, I'm constantly looking for new people to jam with and would love to find a kick ass lead singer. It's really hard to find people outside of your social circle, and that enjoy the same music as you. Your site seems like it could really solve this pain point.
I'd love to be able to create a profile where I can tell people "Hey, I drum, I like metal, I can jam these days, I live in this city, lets play some music". Metallica was created when Lars / James put an ad in the newspaper, the other answered, and the rest is history. Now imagine, this sort of connection on Fandalism.
In terms of monetizing, I think you could use a sort of 'first look' approach like American Idol. If a band forms via your site and continues to use your platform, you could offer to sign them to your label, and give them more exposure on your site.
Another platform that comes to mind, is online Karaoke. American Idol, in essence, is a giant Karaoke fest. Nobody's singing their own songs. If you could create a platform where singers choose a song, and have the lyrics stream across the screen while they sing, you might be able to find some great new talent.
It's important to distinguish between PhoneGap's performance, and the performance of jQuery mobile or Sencha Touch, which are more responsible for the native sliding and scroll features of the non-native apps.
In my experience with PhoneGap, the framework does a great job of exposing native features of the iPhone, i.e. recording audio, taking pictures. The downside for me came only came when adding the visual effects to mimic a native iPhone app. Trying to fix all of the quirks with jQuery mobile, such as persistent headers and footers (although the latest RC has been looking much better), has ultimately led to my abandonment of the non-native app.