More than 1,000 technology vendors are in Las Vegas this week to participate in the 2012 Healthcare Information and Management Systems Society (HIMSS) conference. The annual event comes at a pivotal time for the IT sector. The Department of Health and Human Services is expected to release proposed rules for Stage 2 of its Meaningful Use incentive program for adoption of electronic health records. National health IT coordinator Farzad Mostashari, M.D., will deliver a keynote address Thursday morning.  And last week, HHS secretary Kathleen Sebelius told reporters her department might delay the deadline for complying with the ICD-10 diagnostic coding regimen.