POIs - show on the map?

Yes, but you have to be zoomed in to a particular distance for them to show up. For example, on my Zumo the Custom POIs don't show up until I am zoomed to 0.3 miles or closer. The built in POIs don't show up until I am zoomed to 300 feet or closer which in my opinion is pretty much unusable while driving.

Other units have different settings.

Setting a distance alert in POILoader when loading the custom POI's makes no difference?? On my 2720, I set the distance for the Harley POI's to 5 miles and they show up OK.

On most of the newer models, the alert distance doesn't have any effect on when the Custom POIs show up on the map.

The Favorites on the Zumo will show up at 5 miles, but not anything else.

Many of the nuvis actually won't show the Custom POIs until you are zoomed in closer than what happens on the Zumo.

All that show up on mine are the favorites. How do I get the other POIs to show up?

On the c530, it was 300 feet, on my nuvi 350, it is 200 ft.

If you mean the pre-loaded poi;
You can't while in the Navigation mode.
You can while in "Browse Map" mode.
For custom poi...keep reading.

If one would like to see icons for "custom" poi then you must also load a custom bmp for that file. Otherwise, you'll just get a gray dot.
Instructions can be found by clicking on "Icons" at the top of each page then scroll to the bottom.

As mentioned in other posts, it seems that units differ as to which zoom level poi/favorites are visible.
My C550 must be zoomed to 80,120,200,300 feet for icons/bmps to be seen, or Favorites. 500 feet and higher, nada.

Does anybody know what zoom level the Nuvi 660 needs to be at? I have dowloaded POI's for rt66. I am going to try to do the illinois portion sometime this fall.

200 feet for the 660