haha, found it already!... No, I replaced the stubby am/fm antenna with the shark fin... the second antenna you see there is a very small mag-mount two-way Ham Radio antenna, I have an Icom dual-band 2-meter/70cm Ham radio transciever mounted in the car... you can see the head unit with the yellow display mounted just below the clock:
...and no, it ain't no CB... Breaker Breaker 1-9!
My FCC Amateur Radio callsign is N3LTP. Lol, I tell everyone the LTP stands for "Loves To Party!"
Kingofbeer, I did the same thing, I got my shark fin on a bit crooked... You can buy a replacement pre-formed 3M tape gasket for just $8 from VisualGarage, I had emailed them about it... just cut the fin off the car with a piece of string, scrape the old tape off and stick on the new gasket tape, and re-install - a bit more carefully!... I just never got around to buying a new gasket, so mine's still crooked. No one notices unless I point it out, though, so I just keep my mouth shut, haha...
If you live out in the country and/or your radio stations are more than 10-15 miles away, you WILL notice a difference in the performance - the Shark Fin's tiny little fractal antenna is not nearly as good at reception of distant radio stations as even the stock antenna... a lot more picket-fencing (signal fluttering in and out very quickly)... but it looks great, so it's a fair trade-off in my opinion!