Nokia Lumia 800 and 900 owners, listen up: Nokia has confirmed that it is rolling out the Windows Phone 7.8 update from today. 

The new update, which adds things like customisable Live Tiles sizes to the Start Screen, will come in the guise of a software update to your phone over the next month.

O2 in the UK previously confirmed that 30 January would be the magic day, and it looks like Nokia has come good on the operator's word.

"And now, following extensive software testing, update notifications will begin to appear for Nokia Lumia 510, 610, 710, 800 and 900 owners with an unlocked phone or operator approved software during February," says Nokia on the news. 

According to the Finnish company: "Starting today and rolling out over the coming weeks, a message will appear on the phone encouraging users to get the update. Simply connect your phone to your computer via Zune for PC, or the Windows Phone app for Mac – and follow the on-screen instructions as shown in the video above."

Windows Phone 7.8, which won't be part of the upgrade path to Windows Phone 8, still brings a number of WP8 features to the18-month-old phones. These include internet sharing, Bluetooth sharing, imaging enhancements such as Camera Extras, and the release of apps such as Contact Share, Play To and Nokia City Lens. In addition, there are new options available on your lock screen, such as having a daily background image from Bing; plus there’s improved pocket and child lock screen security.

Delivery of the update is operator dependent, meaning you will receive a notification in the coming weeks if you have an unlocked phone or if your operator has approved the update. 

In the meantime, you can ensure you don’t miss out on the update by checking that notifications are enabled on your phone. Go to Settings > Phone Update > “Notify me when new updates are found”.