If you want to update more than one div, rjs is the best way to go.
For example
def some_method //some stuff render :update do |page| page.replace_html 'div1', :partial => 'partial1' page.replace_html 'div2, :partial => 'partial2' end end
Or you can put these calls in a rjs file (which has precedence over a .rhtml file).
Greetz,
Joram