Some interesting figures to go alongside our story last Friday on sales of the Nokia Lumia 800. Data regarding activations of Facebook accounts with its Windows Phone platform shows a recent lift in numbers throughout this month.

WMPowerUser which closely tracks the progress of the Windows Phone platform, has done its own sums and is saying that over half a million (600,000) new phones have been activated from the 11th of November to the 25th.

Given that Facebook integration is central to the Windows Phone experience (especially in the post-Mango world), we think its fair to say that this is a fairly accurate measure of just how many Windows Phones are out there in the big wide world.

Obviously sales of the HTC Titan and HTC Radar must account for some of these numbers, ditto the Samsung Focus S and Focus Flash. But it’s the Nokia Lumia 800 that’s been released more recently and has been more aggressively promoted.

Sales of the Lumia 800 are expected to ‘slow burn’ over the Christmas period, so this upswing in activations may continue instead of spiking and falling.

Another interesting point to note; a quick look over on Vodafone’s Lumia 800 pre-order page shows that the offer of £60 vouchers still applies. The first 10,000 punters to sign up for a Nokia Lumia 800 from Vodafone will nab the vouchers. That the offer’s still standing practically confirms that less than 10,000 has been sold.

Vodafone wouldn’t confirm with us how many it had sold, though it did say it was expecting a lot of interest in the Cyan edition, which is still only available on a pre-order basis.

Source: WMPowerUser via Phone Arena, Vodafone