A number of names associated with the cloud computing space are trading lower after Rackspace (RAX) reported Q4 results that missed analyst expectations last night. Rackspace, an open cloud company that offers enterprise-level hosting services to businesses, reported Q4 EPS of 21c against analyst estimates of 22c, on revenue of $352.9M against analyst estimates of $355.42M. Although revenue rose 25% in Q4 year over year, the rate of growth is seen as decelerating for the company. Stifel Nicolaus downgraded the company this morning to Hold from Buy, citing the slowdown in growth. In late day trading, Rackspace is down over 20% to $59.87. Other cloud computing names trading lower today include Brightcove (BCOV), down 1.6% to $6.74; Aruba Networks (ARUN), down 4.7% to $21.16; and VMware (VMW), down 3.08% to $74.35.