That is more people than are found of most constituencies in Kenya.
I suspect we shall be seeing very serious traffic jams snarling up our already congested (and potholed) roads over the next two weeks.
That's the downside
The upside: 100000 more people (perhaps) getting to know Kenya and it's attractions for the first time meaning possibly greater improved tourism earnings for this year.
Business opportunities: imagine the guy(s) who has won the tender to print out badges for all delegates at the conference, or the photocopying and catering services as well as the people helping out with logistics and getting paid what looks like a fair amount of money per day.