Bit of a grey area this. I don't see anything wrong with being a 'nice guy', where problems arise and you get trampled all over is when you become a weak and feeble guy who is a push-over.

I consider myself a nice guy, this serves me better than being a dick, allowing me to form friendships, establish good working relationships with colleagues and generally be thought of in a positive manner.

When you hear women talking about their ideal guy, many will say they are looking for a 'nice guy'. By this they mean they want someone like a fireman, a guy who is selfless, brave, has good values, takes care of others yet has a backbone and a masculine essence.