> Why isn't anyone discussing going with IBM's ThinkBlue > version of Linux, > especially looking at 64-bit implementations?
ThinkBlue's actually a separate company, not at all part of IBM. Wrt to 64 bit, there really aren't that many applications that need 64bit addressibility (SAP aside -- but then again, SAP needs all the resources you can possibly give it and then some...). Most things that need that kind of data in memory are CPU hogs that don't perform well on the 390 anyway -- think computational fluid dynamics problems, or stuff like that -- and other than the gee-whiz factor of 64bit, there's not much reason yet to go there. You get more bang for the buck with a gaggle of small 31-bit machines under VM than trying to do large monolithic 64-bit guests.
