XDV/Diazo themeing is very fun and very easy with collective.xdv. We upgrade our website to Plone 4 within couple days.
Again statistics show how secure Plone is. Plone has during the last 5 years been the most secure CMS and today it showed how a vulnerability should be handled.
INCF International Neuroinformatics Coordinating Facility needed a new Plone provider. They didn't just take our word for it but straight away gave us the challenge to upgrade their site to Plone 4.1. We had never seen their site before, but we accepted the challenge.
This year the Plone conference will be held in San Francisco and there are only 400 tickets available so make sure you book your ticket now! This year the conference will deal with related technology track, like Pyramid and Django.
Due to unfortunate circumstances Sipri lost their Plone competence and they needed help fast to upgrade and get their existing site in order. This especially as it had come a couple of security patches to Plone.