Camera phones are the death of the cheap P&S, and thank goodness for that. Hopefully soon the only thing you will really see in P&S cameras are action/sports ones (waterproof, shock proof, etc.), and high quality ones for reasonable prices. That being said, here are my thoughts on the biggest reason the iPhone image is better.....
When it comes to IMAGE QUALITY from photography hardware the order of importance is:
Lens
Sensor
.
.
.
(way down there....)
Everything else.
The Powershot 260IS has a 20x Super-Zoom lens. The iPhone has a Prime in it. So already the iPhone has a massive lead.... I mean an absolutely astronomically large lead, just from that alone. And given the size of the sensor they can put a very good quality prime lens in there for cheap too.
The Powershot has a sensor that is probably 4 times larger than the iPhone. That helps a bit, but it doesn't come even vaguely close to making up for the difference between a 20x super-zoom lens and a prime.
So the problem is not so much the P&S itself, but the fact that it is a super-zoom P&S that has compromised image quality built right into its design. Up side is that the Powershot can zoom in on things much further away and still get a mediocre shot while the iPhone can't get a shot at all.
My advice to the OP would be to get yourself a quality 1-5x Compact/P&S instead of a (relatively) cheap super-zoom. That will get you way better photos than that iPhone. Also get an Eye-fi card and have it upload wirelessly to your smartphone automatically and you too can post photos to FB a couple minutes after you take them.
For instance, here is a SOOC Jpeg taken in similar circumstances to your shots (full auto mode too). Difference is mine was taken with a camera that doesn't compromise in lens or sensor quality nearly as much as yours. Indeed, it is actually as good or better than consumer DSLR's from just a couple years ago (Better than the T1i at the very least in my opinion).... My wifes Fuji X10 (4xZoom, f/2-f/2.8, $450 shipped as open-box with warranty just three weeks ago):
| IMAGE IS A REDIRECT OR MISSING! Byte size: ZERO | Content warning: NOT AN IMAGE |
And just for fun, the pizza we were waiting for when that shot was taken. Sparta's Pizza... The cheese is absolutely ridiculous. If you ever visit Seattle you need to try this pizza:
| IMAGE IS A REDIRECT OR MISSING! Byte size: ZERO | Content warning: NOT AN IMAGE |