See also "Why Should Telcos Build their Own CDN?" - here and posts on Verizon (here), BT (here and here). See also "F&S: Video Delivery, Caching and CDN Markets CAGR (2010-15): 40%" - here.
Nevertheless, with its product offering Akamai will join a growing list of vendors already offering Caching/CDN solutions, including: Alcatel-Lucent (here), Cisco (here), Juniper (here), Ericsson (here), Bluecoat (here), Huawei (here), PeerApp (here), Oversi (here), Bytemobile (here), BTI (here) and Allot (here).
Back to Akamai's move: "With many carriers starting to spend serious CAPEX dollars on their own content delivery build-outs, some are telling me that they don't see the need to allow Akamai to take up more space inside their network .. As soon as carriers and ISPs build and deploy their own CDN solutions, which we have started to see them do thanks to the success of services like Netflix .. Akamai's servers become less important for some of these carriers".