In order to trust IBM's 2015 projections, it's important to see how they've delivered on their 2010 promises, made back in 2007:
The team's presentations are all a must-read.
Palmisano's "strategic overview" is quite short and light.
Financial Discussion by Mark Loughridge, much more in depth. I'd note that they see other tech companies' margins, and see opportunity, especially as software jumps another 50% in terms of revenue mix...
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