got my xoom back from motorola tuesday, for the upgrade to 4g. took about 5 buisness days for the entire process, incl. shipping. so far, everything is working great, no issues to report. its super fast on verizon's 4g network. getting d/l speeds of about 25mbps and u/l speeds of about 5mbps. very happy with it so far... thought i would share this with any one wondering about the process and performance of up grade.