MSIs Notebook Product Manager Neo Lin has let loose a few details on the companys upcoming U91 and U120 netbooks during an interview with Impress a short time ago.
As the direct successor to the U90, the U91 sports an 8.9" screen whilst the bolder U120 uses a 10". Both netbooks will also offer HSDPA connectivity.
Apparently MSI put serious consideration into going with VIAs Nano platform for these netbooks, but decided to go the Intel route instead with a chance of going with the dual-core Atom 330 (providing the battery guzzling issue can be rectified somehow).
2GB was briefly mentioned as being the likely amount of memory to be found in the U120; no mention of actual specs or how/if the U90 will be under-cut in some of these areas. 2GB memory will mean Vista is enforced due to ULPC constraints, which some won't be enthralled about, i'm sure.
You can read the full interview with more tid bits here.