Granite is one of the most durable and hardwearing natural stones available. As long as your granite worktops are manufactured, templated and installed correctly they will give you many years of enjoyment.
Granite is very slightly porous, so you have to ensure that you treat it with care. Especially the lighter colours as the graining in these colours are not as close nit and tight as the darker colours. Therefore they are more prone to staining from red wine, vinegar, acidic and alkaline liquids if these are left on the worktop for long periods of time. As long as any spillages are cleaned immediately you should be fine or if you are really worried I would recommend going for a darker coloured granite worktop. Also to help combat this all your worktops are sealed twice, once when they arrive in the factory as large slabs and then when they leave our factory. However sealing your granite worktops is not a magic cure that will make them impervious to any liquids, so care should still be taken.
Granite worktops are scratch resistant to some degree, but I would never recommend cutting directly on the granite surface. Due to the fact your granite worktop surface will be highly polished on a diamond polishing line, this polish can be tarnished with a sharp knife. Therefore I would always recommend cutting on a chopping board, which for aesthetics can be quite often made in the same granite as your worktops.
As granite is a natural material it can quite often have pitting and fossils in the material, this is no way a fault in the material. Rather it is part of the natural beauty of the stone, similar to the fact wood has knots in it. Chipping should not be confused with pitting, as chips are normally large. Your granite worktops are extremely hard and will not chip under normal circumstances. However if external induced force such as dropping a mug on a weak point of your worktops such as the edge can cause it to chip, chips can normally be repaired.
Finally I am quite often asked the question that as granite is heat resistant can I put a scorching hot pan on it directly from the oven. I would never recommend putting a scorching hot pan directly on your granite worktops. Due to the fact granite can suffer from heat shock, which is caused by the rapid temperature rise from its normally cool surface. Therefore I would always recommend using a trivet or tripod when placing a hot pan on your granite worktops.