can't get multiple lines with tikz-qtree package

Question

I am using the following code to draw a fairly simple tree. The problem is that the line break commands are being ignored although I have found a number of examples on the net that show that they should work. What I am getting is the figure below. I am not sure where my problem is and would appreciate any help.

\documentclass{article}
\usepackage{tikz}
\usepackage{tikz-qtree}

\begin{document}
\begin{tikzpicture}
\tikzset{level distance=40pt, sibling distance=10pt}

\Tree [. {MapReduce Join \\ Implementations} 
    [.{Equi-join} 
        [.{Repartition Join} ]
        [.{Semijoin} ] 
        [.{Map-only Join} 
            [.{Broadcast join} ]
            [.{Partition join} ] 
        ] 
    ] 
    [.{Similarity join} ]
    [.{Multi-way join} 
        [.{Multiple \\ MapReduce \\ jobs} ]
        [.{Replicated join}  ] 
    ] 
]
\end{tikzpicture}
\end{document}

Answer 1

Never mind... I should read the manual more carefully. The following solves the issue:

\tikzset{every tree node/.style={align=center,anchor=north}}

Sorry for taking up bandwidth.