The 800/1500 double is extraordinarily hard and achieving silvers in both is quite a performance. I wouldn't be surprised to see his 1500 upgraded to Gold within the next year, given what we already know about Centro and NOP.
Combine this silver duo with his 2012 Gold and African champs medals and you're looking at quite the exemplary career. Hope to see more out of this smiling jovial man in the coming years.