Summary: In vChat #18, Simon, Eric, and David discuss Simon using Twitter at Mt Everest basecamp, the new Iomega PX4, HP Discover, HP TouchPad, Uber EMC VNX VSA, the Denver VMUG, the VMware Cloud Infrastructure Launch Event (July 12), VMware vExpert program, VMworld 2011, and new TrainSignal VCA-DT and Security products.