Looking outside and seeing people get wet as they go from their car to the lobby is observation. Noting that you could put a place to borrow/leave umbrellas in the lobby and near where cars park is an insight. Figuring out that the reason they are coming and parking and going into the lobby can be re-interpreted so that they don't have to leave home/office and even bother getting wet is a 'deep' insight.

The link that pg gives to the drobbox app is full of win. It isn't about shared storage 'per se' its about the things that currently suck and will suck less with less effort when this capability is available.

Insight is looking past the problem and finding the underlying intent, and then re-working the solution based on that intent.