5:20 AM
Finally a new version of the pullquote package up!
I completely redid the user interface: environment with KV options.
More configuration options.
@AndrewStacey You can configure the vertical position now :-)
Some user documentation. In particular, I included some comments by @speravir concerning Windows usage. It would be great whether someone could confirm it works that way, as I can't test on Windows at all.
Based on this version, I will now release more frequently again ;-)

2 hours later…
7:27 AM
I've worked in background on the question and now the result got seems a bit strange (at least I'm not able to motivate it); in the following example, nodes are numbered with the same approach derived by Jake and two "hobbies" path are establish: one by the command \hobbyconvexpath and the second one manually. This ends up with:

8:01 AM
The link of the minimal working example: dropbox.com/s/ep1t9be32ezmst4/prova_hobby.tex

8:38 AM
@AndrewStacey One more remark on the pullquotes package: By your request, I changed the control flow for \textcolwd so that it is now calculated at the start of the environment. So it will adapt to the current linewidth now.

9:21 AM
@StephanLehmke Section 2.2: "unsing" -> "using"

@AndrewStacey Thanks, corrected.

@StephanLehmke Figured I'd better actually read the instructions! And I got my pullquote working correctly on the first go (modulo the \noindent needed before it). You seem to have left the "write lots of stuff in my log file" option on again. Remind me what I need to do to turn that off.

@AndrewStacey Just update ;-) I got a strange conflict with my last merge which seems to have deleted some recent changes :(

9:42 AM
Ever-so-slight overlap at the bottom with the italic text; otherwise, perfect.

9:53 AM
@ClaudioFiandrino The main problem is that you are using open paths instead of closed paths. When I close the blue curves then I get a better fit (something's a bit odd with the placement of the g and f nodes, though). Fixing the automatically generated curve takes a bit more work, though, because the \foreach forces a new curve segment for each time (this is a limitation of how the "quick parser" works).
An alternative would be to use the foreach to construct the curve but then evaluate it afterwards. Or you could use a different method of invoking the hobby constructor: it works by passing it points so just pass them directly.
\documentclass[tikz,border=2bp]{standalone}
\usetikzlibrary{backgrounds,calc,trees,hobby}

\pgfdeclarelayer{background}
\pgfsetlayers{background,main}

\newcommand{\hobbyconvexpath}[2]{
[
create hobbyhullnodes/.code={
\global\edef\namelist{#1}
\foreach [count=\counter] \nodename in \namelist {
\global\edef\numberofnodes{\counter}
\node at (\nodename)
[draw=none,name=hobbyhullnode\counter] {};
}
\node at (hobbyhullnode\numberofnodes)
[name=hobbyhullnode0,draw=none] {};

@AndrewStacey For the overlap you could file a bug report. This shouldn't happen... Or are you getting an overfull hbox message?

@StephanLehmke You would not believe how many Overful/Underful hbox messages I have in this document! I'm ignoring them at the moment as I've squeezed the document into a small shape to make it easier to read on the screen. But, yes, one of the overful ones is that line so it's not a fault of your package but rather that my constraints are too much for poor old TeX.
        mag=1732,
paperwidth=20truecm,
paperheight=20truecm,
height=19truecm,
width=19truecm,
includefoot,
foot=\baselineskip,
truedimen

@AndrewStacey Still I explicitly set \tolerance9999 in the text so I'm surprised it happens. I've also seen some bad lines before setting \selectlanguage{latin} for the \lipsum text, but always on the "stretched out" side, never an overlap.
Maybe there is no hyphenation point for the word "smoothly"?
Maybe I should also set \emergencystretch... The word "spaces" is also sticking out in the second column.
I'll certainly experiment a little more for the documentation and give hints on typesetting tricks.

@StephanLehmke Plausible. I'm also using luatex with fontspec and the TeX Gyre fonts. I seem to get quite a lot of overful/underful stuff with that combination, but at the moment I can't be bothered to debug it as I'm more concerned with the contents (modulo the odd strange bird).

@AndrewStacey Ok, this almost certainly means no microtype features. That explains a lot. The hz algorithm is a real life saver in such tight columns...

10:08 AM
@StephanLehmke When I compile it with full page size then I only get underful hboxes.

10:24 AM
@StephanLehmke Just downloaded the beta version of microtype with more luatex support and it fixes that box (at the expense of a wacking huge overful in the second column!).