Guinea-Bissau and The Gambia
 

There isn't much travel to these two countries by overlanders.

Is there any good reason for that or are these two countries just too boring/dangerous or some other good reason for not going?

Those that have been, what are some of the "Do not miss!" places to see and things to do in these countries?

I wouldn't say dangerous.

My experience Feb2011:
In Gambia our biggest concern was corrupt policemen, in Bissau the biggest danger comes from not having public lights at night (the risk is just falling into a hole without seeing it...)

Very friendly people in Guinea-Bissau.

Some pictures on the link below. Further questions please feel free to ask.

BR,
Luís CaBRita