My first reaction was, “Nice work!” I like the colours and the clear organization.
Personally, I would try removing the boxes around each section, maybe creating boxes around each column (so there are no horizontal bars).
I’d also want to fiddle with the lower right box to make the bottom edge align with the other two boxes. This poster does such a nice job of keeping things clean and aligned that little things like that stand out!
I like using bold to emphasize key points, but I wonder if there might be a little too much bold. The less you have, the more punch each instance has. It’s diluting some of the impact.
The very top box is a nice attempt to introduce the problem, with sort of a sub-headline. But it doesn’t have any other clear signals to its importance apart from its position. It comes across as a small sliver of text, and your eye hops over it to the first box in the top left. It might benefit by being made larger, or using something else to distinguish its place in the poster’s information hierarchy.
Looking at this from a distance, it feels off kilter, because of the asymmetries in layout. There are uneven columns, and the logo on the right is also breaking the symmetry. I suspect that the title is truly symmetrical when measured with a ruler, but it looks like it’s too far to the left. The normal expectation is that the title will line up with the central column, which is pushed right because the right column is narrow. I suggested making the title aligned to the left (perhaps enlarging a little), and putting the authors and institution on one line below that. Then it could be roughly the same height as the institutional logo.
Here is Ciaran’s revised version:
I followed your suggestions, except for removing the horizontal bars: I couldn't get that to look right. I ended up coming second place in the vote at CP 2014 (http://cp2014.a4cp.org/), which was a pleasant surprise.