If you're going to have to type up more of these tags, the listings package may be well worth a try (employing colors for operators (or literals, or whatever) is tricky; if you'd like them, usually, one suggests the package minted, which unfortunately does not do inline stuff! catch 22!):
\documentclass{article}
\usepackage{listings}
\begin{document}
\lstinline[language=xml]!<tag>!
\end{document}
Some remarks about the code:
! is a delimiter for the code that goes between its two instances: so, this should be a symbol that does not appear in the code (cf. | that appears in \verb command in m0nhawk's solution). So,
\lstinline<<tag>< % wrong
\lstinline><tag>< % not wrong, but not what you want
\lstinline$<tag>$ % right
\lstinline+<tag>+ % right
\lstinline|<tag>| % right
The delimiter cannot be this [ unless you do the following:
\lstinline[][<tag>[
(What is happening is that, the \lstinline looks for an optional list of key=value pairs, when it first encounters [.)
I am posting this answer, mostly for the reason that, using \verb, you end up with different font family, which may well be your desire! In case, you'd like the same font family, this solution is open.
Output: