The open-source CMS, Midgard, is hanging in there. Real PHP weenies (we count ourselves among them) like the fact that that Midgard is highly extensible. But as an interesting new case study shows, you should be prepared to spend a lot of developer time to get it to flex to your particular needs. In this respect, Midgard -- like most of its open-source peers -- resembles higher-end commercial offerings...
Read the Case Study (evidently from New Zealand)