Just like its scientific namesake, BT's Fusion service seems to be taking longer than anticipated to reach reality.
Despite the promise of "the service being widely available for delivery in September" (and this confirmed by me in a call a month ago with BT FMC guru and FMCA supremo Ryan Jarvis), it still seems to be at the stage of soliciting customers to "register interest". There's certainly been no fanfare or even press release to note its passing into massmarket deployment.....
No particular clues on what's causing the delays, but I have a suspicion that the installation in customers' homes (especially if it means the user ditching an existing ADSL modem & WiFi AP, with all the PC and software reconfiguration that entails) may be a culprit.
It also wouldn't surprise me if BT's MVNO relationship with Vodafone has made it more tricky to do the network-side integration than might have been the case with an in-house cellular network. The MVNO deal with Voda is certainly "deeper" than the average "consumer brand capacity resale MVNO" affair, but the emerging dual-mode handset / "seamless roaming" architectures need some pretty tight coupling with various bits of cellular core network gubbins like MSCs and HLRs. And of course, nobody could possibly imagine Big Red only playing precisely by the T's and C's? Surely they'd willingly go that extra mile to help out a key partner launch a flagship service if necessary?