The situation is different for me: almost every customer I have had in the last 3 or 4 years has at least partially used AWS so I have already gone through the learning curve.
Your point on vendor lockin is certainly valid: if you really take advantage of AWS services, you are locked in without a porting effort (like AppEngine).
Your point on vendor lockin is certainly valid: if you really take advantage of AWS services, you are locked in without a porting effort (like AppEngine).