This page it PACKED with info! Here is how to get the most out of it.
First, check out the map. In the upper right corner you will see the square "Layer Button". Click it, you will see a list there of the different maps available. Click through them to see what is available.
If the marker is near civilization try the "Places" overlay in the "Layer" selection. This uses a Google Places search for the things cruisers want like shopping and ATMs.
Now check out the "Full Screen" button. Try it out, especially nice when viewing the Navionics Charting layer.
Now check out the weather forecast. Click on the map to select an area, you will notice a movable indicator that will display the weather information where you clicked. Feel free to drag it around. Lots of good weather information here, play around with it.
And last, but not least. Take a peak at the current tides.