The Sony Ericsson Xperia X2 (Rachel, as it's called) will have a WVGA (800x480) screen and will run Android.
Software-wise, Android is capable of any framebuffer resolution on any device (hardware and memory resources permitting). It's known to run in 1024x768 on desktop/laptop PC's, too.
Current: HTC Vision/G2, HP Touchpad, MOTOACTV watch.
Previous: HP Veer, Galaxy S Vibrant, HTC EVO 4G, Kaiser, Wizard, Blackberry Curve, Nokia 2115i.
ROM Projects and experiments:
Open-source/free-software UEFI loader for HP Touchpad and Qualcomm ARM.
Working on an AOSP-based MOTOACTV ROM.
Doing random experiments with openWebOS, FirefoxOS, and Haiku on ARM.
If/when I get a hackable Intel phone to test with, it'll get some dev.