Can anyone knowledgeable comment on the depth of Kenya's internal divisions?

From the NYT's perspective clearly Kenya is racially uniform, but I know that there was significant political violence at recent elections, to do with which tribe or language group candidates or parties represented. Do such distinctions matter only at voting time, or do they matter in everyday life too... like whether X landlords will be happy to rent to Y people, or employ Z? Can such distinctions be perceived immediately on the street (e.g. from accent) or only once you know someone's surname, or something?