The E-PL5 has a much better image quality, DR and AF and it is quicker than my old (and sold) E-PL2, see and read here http://www.pbase.com/ltolksdorf/image/141209953. It is a worthy upgrade.
I really love the Pana "Leica" Summilux 25mm. In my opinion a must have lens for m4/3. It extend the application of the Pen because of the small dof (like a f2.8/50mm in Full Frame). And it is sharp even at f1.4 and has autofokus.
The main advantage of the Pen it is small size and weight bond with the very good image quality. So I have taken most of my favourite shots with this system. Not with my Leica or Nikon.