No, stagnant would imply things were stable and they're clearly not. You can make an argument that Symbian OS was successful in the past, but the trend in the G

No, stagnant would imply things were stable and they're clearly not. You can make an argument that Symbian OS was successful in the past, but the trend in the GigaOM chart you linked is pretty clear: rapid decline. In 2007, Symbian was around 2/3 of the total smartphone market, and two years later it had fallen below 50%. During the same period, RIM almost tripled its market share and the iPhone and Android numbers were showing even stronger growth.