If safaricom have no intention of amending the pricing strategy they will surely get bruised by Yu and Zain. I'm looking at my safcom line which is currently at 8bob a minute...doesn't it make more sense to call from zain/yu to safcom than safcom to safcom? Either way people will not ditch their safcom lines in the short term largely because of the financial aspect (mpesa/mkesho)...but they will get additional lines in the rival networks. Therefore Zain and Yu will record significant increases in registered lines and ARPU while safaricom might see limited customer churn but they will take a hit from reduced ARPU. The fact that the network quality on Zain and Yu is better than safaricom's doesn't help the queen bee at all. However, the financial domino could fall flat on safaricom in the longer term as more people have lines on Zain & Yu and more merchants partner with the two for payment services...see where this is going?
On another note, I have not noted any congestion today when calling safaricom from zain. Seems they heeded the call...