Ask or Answer.

I received an email from "Schmap Guides." saying that they were going to use a photo of mine that is posted on Flickr,

"Clicking this link will take you to a page where you can:
i) See which of your photos has been short-listed.
ii) Submit or withdraw your photo from our final selection
phase.
iii) Learn how we credit photos in our Schmap Guides.
iv) Browse online or download the fourth edition of our
Schmap Glasgow Guide.

While we offer no payment for publication, many
photographers are pleased to submit their photos, as Schmap
Guides give their work recognition and wide exposure, and
are free of charge to readers. Photos are published at a
maximum width of 150 pixels, are clearly attributed, and
link to high-resolution originals at Flickr."

Is there a "con" here or is it genuine?

I'm sure most of us have been in this situation: you're helping a friend shop for a new pair of trousers and they try on a very fashionable pair, reduced in the sale, and YOU THINK they are completely unflattering and make their bum look the size of a small country. They then ask you the dreaded question:

Cheers, Tom.