Q:

How to highlight paragraph (linebreak preserving) as well as itemize, tabular etc.? 

I want to highlight changes which are introduced by myself in the pdf document.  So far the soul package is very neat but it does throw errors when I want to highlight not only paragraphs but also some itemize environments, and I don't want to highlight the items separately.  Also the \cite{...} command is not supported by \hl.  I recently posted a slightly different question: Change text background within paragraph (with automatic linebreaks)
BTW: What I liked most over other approaches like pdfcomments etc.  is that the \hl command from soul has a very exact and clear output, no icons, no clicking etc.  involved.  Together with todonotes it's very good and almost all I need. 

A:

Concerning your question about \hl support for \cite: while \hl{text\cite{book}} gives an error, it works if you additionally group the \cite command by curly braces. 
\documentclass{article}
\usepackage{soul}
\begin{document}
\hl{text{\cite{texbook}}}
\begin{thebibliography}{Knuth86]}
\bibitem[Knuth86]{texbook} D.E. Knuth, The TeXbook, 1986
\end{thebibliography}
\end{document}

gives

