I stayed at the Crown Plaza in mid February for one night during the week for business. Being centrally located in Nairobi's financial district (as opposed to town centre where the Interconti and some other hotels are) the Crown to me is the best hotel for business travellers whom location is important.
Crown has all business facilities that one could need. I had access to the club lounge floor with its own complimentary business centre and f&b. There is strong wireless connection everywhere making it easy to work virtually anywhere in the hotel. There is a fully equipped business centre, a bank (DTB), a couple of small meeting and conference rooms, as well as very big banquet halls with good conference facilities. During my stay there was a conference going on - the Alabaster lounge just outside the banquet halls serves excellent tea and pastry and was my favourite 'work station' during my stay.
The gym is really good with very modern equipment. They have a small pool as well that faces the main breakfast restaurant, but being outdoors I didn't use it.
All in all, I had a very very convenient stay at the Crown. The hotel has a own taxi fleet which I used to attend a meeting and for my hotel transfers. If you stay longer and have a free afternoon or morning, the travel desk organises day trips to the nearby game park as well as more farther places.