On 28th of April, Greg Stark committed patch:

Add support for wrapping to psql's "extended" mode. This makes it very
 
feasible to display tables that have both many columns and some large
data in some columns (such as pg_stats).
 
Emre Hasegeli with review and rewriting from Sergey Muraviov and
reviewed by Greg Stark

The description seems to be easy enough to understand, but let me show some examples.

Normally, when dealing with huge values you get output like:

Standard idea for improvement is usage of extended mode. This gives:

there is so much free space, because later on it looks like this:

Not so cool. Now, with this patch, after doing:

\pset format wrapped
\x

output looks like:

I would say that it still needs some polishing, but it's much better than it was before. Cool. Thanks.