Some writeups of the conference:

MathsJam Conference 2015, by Peter Rowlett for MSOR Connections

A Non-mathematician at the MathsJam Weekend, November 2014 by Rachael Wright

Here are some of the testimonials received after the 2010 MathsJam. There were many, many more emails that expressed similar sentiments.

Mathsjam 2010 was huge fun. The best part was the quickfire presentations, which ranged widely - odd socks and unsolved knot problems, lemmings and vampires, pulley balances and platonic reflections - and a touching tribute to our missing friend, Martin Gardner. There wasn't a single talk where I didn't learn something new. More please!
Mike Frost

People thought I was mad when I announced that I was going away to do maths for the weekend - and pay for it! But the Maths Jam was the most stimulating time I could have imagined. Some of the presentations started out as problems I thought I knew all about, but then they took a subtle turn into unknown territory changing an old friend into something new and fascinating. I confess that some of the maths went way over my head, but far fewer than I'd expected and anyway, that just gave me more time to think about the ideas that interested me. Unfortunately I'm not currently teaching in a school, but if I was I'd have gathered enough good ideas to keep all my classes happily playing with maths for a long time. Roll on 12th November!
Lucy Sayce-Browne

MathsJam is the most fun conference I've been to. An enjoyable, relaxed environment where friendly people share interesting puzzles and mathematics. This isn't just for puzzle experts - all levels of expertise are warmly welcomed. Short talks mean plenty of variety and lots of breaks give plenty of time for playing with what you've seen and getting to know people. I'll certainly be attending again this year!
Peter Rowlett, peterrowlett.net

MathsJam is a British version of the well known Gathering for Gardner in the US. I've been to both and they are both terrific events, bringing together like-minded souls in an informal setting for thought-provoking discussions and exchanges of ideas. There was such positive energy at the first MathsJam that I'm sure the event will grow, and I'd say that it has already made itself the focal point for recreational mathematics in the UK.
Alex Bellos, Author of "Alex's Adventures in Numberland"

Fun, refreshing and entertaining, MathsJam 2010 for me was how a conference should be. I enjoyed the short presentation format, chatting with the wide-ranging mix of people, and seeing many new and interesting things. A great opportunity to remind yourself why you like maths, or to fall in love with it for the first time.
Francis Hunt

MathsJam is an unforgettable experience. Rarely is such passion together in a single room, with the sole aim of enjoying maths for its own sake. I am gutted that I can't attend this year - but try and stop me next year!
Andrew Jeffrey

MathsJam: a weekend of fun maths, hard maths, origami, magic and lots of very cool people.
Michael Borcherds