This happened to NanoMechs. Its probably because it got approved at night and iTunes only updates in the morning
We're still waiting... 12 hours and counting. Looks like very few apps from yesterday are showing up, must be something going on with their servers. Maybe related to the switch back to top100?
It is up! http://itunes.apple.com/WebObjects/MZStore.woa/wa/viewSoftware?id=330855673&mt=8 (it is not showing up on searches/listings, but at least the link works)