(keitai-l) DoCoMo's i-mode subs descreasing

After years of stable and well respected growth, it seems DoCoMo is 
entering a new phase.

Official DoCoMo stats show that the number of i-mode subs has declined by 
12k in the first week of December.

http://www.nttdocomo.co.jp/corporate/investor_relations/business/imode_j.html

What could be the reasons for this?
1-  KC's campaign against i-mode is finally bringing results ;-)
2 - KDDI's WIN service and Vodafone's latest handsets are so cool, that 
DoCoMo's churn gets higher

Some other thoughts?

Arjen van Blokland