Transaction value (which is not at all the same as GDP, transaction value will be vastly larger than GDP) is much lower for Bitcoin than the outstanding value of the currency is.
It seems reasonable that Rackspace will have the most appeal to SMBs because of the value proposition of outsourced and scalable IT functionality, but this segment is more vulnerable to economy swings than larger enterprise customers.
The one risk in being too negative is the chance that they sell to a larger competitor, though at a nice premium to its tangible book value, the stock is not as attractive as other potential takeover candidates.