Hot on the heels of the popular Sony Ericsson W800i comes yet another Walkman phone, the swivel-action W550i, an enhanced version of the canceled S600i. Sporting the trademark bright orange exterior, this upcoming handset is equipped with several functions similar to its candy-bar predecessor including dedicated music buttons, FM tuner, video and still image capture, and Bluetooth connectivity. Adding to the whole mobile entertainment experience are new features such as advanced 3D gaming support, interchangeable covers as well as a whopping 256MB of onboard memory which lets you store more than 70 songs.

Upside: The key multimedia feature upgrade on this new Walkman phone is the enhanced gaming interface. The W550i's keypad can be swiveled behind the LCD display panel to convert the handset to a portable gaming console. The result: A surprisingly ergonomic two-handed gaming console with a landscape view. Mobile gamers will also be happy to know that the handset comes with enhanced 3D gaming support as well as wireless multi-player capability via Bluetooth.

Design-wise, the W550i's front and back panels are interchangeable, so users can customize it to match their lifestyles. We suspect this feature will appeal to the younger audience, just like some of the Nokia phones. What's noteworthy about the Walkman phone is the addition of extra buttons. Besides the music playback button on the left, Sony Ericsson has also incorporated a spring-loaded switch for one-touch locking and unlocking of the keys. There are also two hidden buttons located above of the screen which can supposedly be used only in the gaming mode.

Our initial hands on with the prototype W550i unit found the LCD display sharp and crisp, with speakers that offered a good volume range for gaming as well as music playback. Like the W800i, sound reproduction on the provided earphones was impressive, too. We expect the W550i to easily last for more than two days on regular usage since it was still displaying an almost full bar on the indicator after its initial charge a couple of days back. The handset construction itself feels solid, from the swivel mechanism to the buttons, which should be added assurance for those skeptical about the durability of the phone.

Downside: Our biggest gripe with the W550i has to be its lack of a memory expansion slot. While it is equipped with 256MB of onboard flash memory (which is perhaps one of the higher storage capacities found on a phone today), the fact that the user cannot add more memory to the terminal will limit its usage as a multimedia handset, be it for music, images or video. The 1.3-megapixel camera is kind of a letdown, too, considering that many of the upcoming phones are sporting 2-megapixel and above sensors.

Some people may find the W550i rather bulky which can be partly due to the extended handle. The handset is also somewhat top heavy when fully swiveled. That said, the phone does offer a comfortable and good grip when gaming. The line up of the number keys in three separate columns may not go well with some SMS texters.

The absence of an onboard 3.5mm audio jack will put off music enthusiasts who want to connect their headsets to the phone, though users can still do so by connecting through the bundled portable handsfree.

Outlook: Despite the above shortcomings, there's still a lot to like about the W550i not just for its eye-catching swivel design, but its powerful mix of onboard multimedia features. From 3D gaming and music playback to still image and video recording, the handset is clearly aimed at catering to the increasingly demanding mobile entertainment crowd. Expected to be launched in late October, we will be awaiting for the actual commercial unit for a full evaluation. Watch this space.