Why does open source VoIP make no news lines anymore?

Open source does not make many headlines anymore because just about all major carriers now use open source VoIP platforms. All major carriers have platforms like Asterisk or OpenSIP or FreeSwitch performing some function in their network. Some are using these platforms for voicemail, some for IVR, some as announcement server, some even for switching.
 
Asterisk and OpenSIP are particularly well deployed in tier 2 market. Tier 1s are obviously not using Asterisk for switching but there are OpenSIP and Freeswitch for routing and switching functions. A good indication of who is using Asterisk is to look at the attendees of Astricon, the annual conference of Asterisk developers and users. You find all major telcos at the event.
 
The carrier market for Open Source VoIP platfroms is by far 10 times bigger than  end users in enterprises. Carriers obviously serve large number of customers. In South Asia there are huge open source VoIP based call center companies using the platform. We are talking multi billion minutes per month in carrier space going over open source platforms.
 
Among the platforms, OpenSIP has certainly carved a niche for itself in carrier market and is ahead of Asterisk in many regards. Open SER / Open SIP / Kamailio is a SIP proxy. Asterisk does not have a full SS7 stack. Asterisk and OpenSIP go well together. Some carriers need just one while other use both. Freeswitch caters to carriers that require both switching and media handling in one platform.