The wireless carrier O2 UK can now lay claim to becoming the first one in that country to offer visual voicemail for some of its Windows Phone products, but the carrier has also revealed that the promised Windows Phone 8.1 update has been delayed for other devices.

O2 quietly launched visual voicemail support for the the Lumia 925, 625 and 1520 on Friday, and as Neowin reports, this will be very handy for owners of those devices. Instead of calling a number to hear voicemails, they can now be downloaded to a smartphone, which should make listening to them easier. The new feature does require Windows Phone 8.1 to be enabled on those phones.

It's not all good news for O2 Windows Phone customers. In their forums on Friday, the company posted a new update on the availability of Windows Phone 8.1 for other devices. In short, O2 is ready to go with the over-the-air updates, but Microsoft isn't. The post says:

"It's important to understand that O2 have already approved all of the 8.1 updates which are sitting with Nokia - at this stage, there's little we can do to speed up the process as the last part of the equation is for the update to be released to customers."

O2 adds that they hope to roll out the Windows Phone 8.1 updates to their other customers starting late next week but added that more delays could still happen. What do you think of O2 becoming the first UK carrier to enable visual voicemail for Windows Phone devices?

Source: Neowin, O2 UK