The climbing is serious, by which I mean it is more like alpine climbing than icefall cragging in terms of how much you should be prepared to rely upon your own skill and judgement. Your worst problem will be the weather, and thus the conditions. Bring a good, thick book. There is lots of accomodation down in the valley, from five star Relais and Chateaux hotels through bed and breakfasts to bunkhouses. These are anything from 1 to 4 hours walk from the base of the climbs, depending on where they are and which climbs you want to do.
Travel is easy, with a reasonable train service and regular buses and coaches from Glasgow.
If you are driving, the roads into the area rarely block for any length of time but exceptional snowfalls might cause delays. You can fly to Edinburgh or the Glasgow area from Frankfurt and Amsterdam. I agree with Jens that the worst problem is usually the descent. Conditions on the summit plateau can be truly awful, and are often much worse than on the climbs, since the North Face is in the lee of the prevailing winds. You must know how to use a map and compass and force yourself to trust them.