What is the difference between a blog and a feature?

Good question.

This is an article I wrote recently on one element of the modernisation in Royal Mail. Some quite nice quotes and an enjoyable piece to write.

Then there's this blog I wrote on the proposed expansion of Luton Airport, near my home.

I guess the latter is a blog because the only research was done online and at the exhibition, without anyone else's voice.

Are the two forms mutually exclusive?