Mandela (any many many others who seem to get forgotten - it wasn't a 1 man mission) did a lot of good in SA turning around the terrible Apartheid state. He deserves recognition for that.
some of his methods though where deployable by any standard. He was a senior member of major terrorist organisation. Killing innocent civilians to support political aims isn't something many people agree with but that's what Mandela supported before his imprisonment.
I'm not saying he isn't someone we can look back on with some respect but I am saying he certainly wasn't a saint. He was a normal human being with good and bad characteristics (just like most of us) and not by any stretch of the imagination the 2nd Jesus/Mohammed (pbuh) some of press claim.