Seems I read a design article once that claimed the /best/ thing you could have for a logo was an abstract shape that consumers identified with your brand, like

Seems I read a design article once that claimed the /best/ thing you could have for a logo was an abstract shape that consumers identified with your brand, like the Nike swoop. It's fairly unique, identifiable, and unlikely to be confused with anything else. Seems the old windows logo was that, the new one is not.