The Vaio UX90PS is identical to the UX50 in every respect with the addition of a TV tuner and the replacement of the 30GB HDD for a 16GB flash RAM HDD. Verdict: the TV tuner and software doesn’t work outside of Japan, but no big loss since there’s only one TV station in Japan anyways. The additional cost for RAM HDD versus a physical HDD is worth it.
At the end of the day, you need to ask yourself if it’s really worth spending over $2K on a device with only a 4.5-inch LCD screen, 16GB of flash RAM, 512MB of RAM and a nearly unusable keyboard. For me, it’s not worth it – yet. I’ll stick with my Nokia E61 smartphone for much of the activities that I’d do on the UMPC and pull out my Macbook Pro as needed.
Nano Review of the Vaio UX90PS (16GB Flash) [Akihabaranews.com]