On 28/03/2008, at 1:03 PM, Paul Thompson wrote:
> Is there some document somewhere which lays out the objectives of  
> the new system?  I have long had some notions which I believe will  
> improve functionality.  Before making them, I would like to see that  
> plans for the system.

I believe the "user interface" to LaTeX3 has not yet been thoroughly  
researched. This is as good as it gets, as far as I'm aware:
   <http://www.latex-project.org/guides/ltx3info.pdf>

However, a lot of work has been done on the underlying programming  
interface:
   <http://www.latex-project.org/svnroot/experimental/trunk/l3in2e/>

I'd like to see a more modular, CSS-lile, interface to most LaTeX  
objects, from section headings to inserting figures. But I'll have to  
finish my PhD before I even start to experiment...

For example: (just off the top of my head)

\section[
   label=sec:title,
   short-name={This is the toc title},
   mark-name={This is the title in the header},
   numbered=true|false,
   in-toc=true|false,
   ...
]{This is the title}

\insertgraphic[
   label=fig:pic,
   display=float|block|inline,
   float=htbp,
   halign=l|r|c,
   caption={This is the caption},
   short-caption={Caption in LoF},
   ...
]{mypic.pdf}

\begin{table}[
   label=...
   display=float|long|block...
   caption=...
   short-caption=...
   column-setup={@{}ccc@{}}
   row-setup={
     1>{\toprule}
     1l{\bfseries}
     2>{\midrule}
     -1<{\bottomrule}
   }
   cell-sep={,},
   row-sep={;}
]
   Bold , Header , Row ;
   1 , 2 , 3 ;
   4 , 5 , 6 ;
\end{table}

Will