Sony Xperia S on pre-order, yours for £21.50 per month

Pre-orders are open for the Sony Xperia S, with prices starting at £21.50 per month, Unwiredview reports.

Aptly-named site buymobilephones has listed the Android-powered mobile with pre-orders for all major UK networks, including O2, Orange, Vodafone, Three and T-Mobile.

The cheapest way to get the Xperia S for free appears to be with O2, which will flog you the Xperia S for £21.50 per month. That gets you 100 minutes, 500 texts and 500MB of data, but it's a 24-month contract, so you'll be tied in for a long time.

Still, for a high-end smart phone, that's not too ruinous. By comparison, to get the iPhone 4S for free on O2, you'll need to pay at least £41 per month, which is nearly twice as much.

The Xperia S will be the first smart phone to arrive under the Sony banner, with the company buying Ericsson out of its partnership in a deal worth £918m. I got to play with the Xperia S at CES last month, and was left feeling cautiously optimistic.

The 720p-resolution screen looked great, and there's a 1.5GHz dual-core processor lurking inside, coiled up like a snake ready to pounce on hi-def movies and graphically demanding games. The translucent strip at the bottom of the phone is an interesting design quirk.

The camera should be pretty decent -- this 12-megapixel number is packing Sony's own Exmor R sensor, a bit of kit that contributed to the earlier Xperia Arc being a brilliant camera phone.

The bad news? I'm sorry to report that the Xperia S will hit the ground running Android 2.3 Gingerbread, rather than the latest version, Ice Cream Sandwich. Heartbreaking stuff.

Hold off on purchasing until you get a peek at our definitive review. While you're waiting, tell us whether you think the Xperia S can outsmart the iPhone. The place for comments is in the box below, or over on our Facebook wall.