Iam not sure if 'new logo / new website' topic is still open for discussion, if yes - here is my proposal.
First, yii is a very good product, elegant and simple - for me this is most important when it comes to solution that will act as a base for my business (apps, sites, whatever). Speed, efficiency and extensibility are also not trivial but they're results of good design, and good design when it comes to frameworks is always about simplicity and elegance.
I think that's yii's USP (Unique Selling Proposal) and it's brand should be created around it. I prepared some drafts of logo based on this foundation, in my opinion yii needs one strong simple (without decorations) symbol that will reflect it's nature.
i think jannki's concept is awesome. i mean a big Y and four dots. but i also think that we can try this concept with a very large set of color palettes, so we find the most perfect one. i liked the proposed colors in general, but in each of them, it's like, something is missing. the very top one reminds me Yahoo, which I think is not a good choice…