We're just back from Sony Ericsson's press conference where they announced that they're filling out their lineup with five phones to be released before the first half of 2010 runs out. The Xperia X10 you've already heard of. Sony Ericsson said they wanted to give that experience, but in a smaller form factor. We can't say that big SE achieved the exact same user experience, but they definitely nailed the smaller form factor.
The Xperia X10 Mini is a tiny little wonder of an Android device, coming in a 83 x 50 x 16 mm and 88 grams. That tiny size does mean a tiny screen - a 2.55 incher with 320x240 resolution. It's powered by a 600MHz Qualcomm 7227 processor and take microSD for expansion, 3.5 headsets for music, and a cellular tower for data connectivity - no WiFi here. You're going to get Quad-Band Edge and two versions of 3G (North American and Global) - though whether SE can actually land carrier deals for the phone is an open question. Talk time should land at about 3.5 hours, give or take.
SE has significantly altered the build of Android 1.6 on the device - it's nigh-unrecognizable and takes a bit of getting used to. However, they've helpfully added 'hot corners' to speed navigation up a bit. Hands-on impressions coming soon!