Don't know of any articles, but some good facts are that they're pretty clean, friendly and really smart. If they were to let you keep any other pet, there's no reason not to let you keep rats.

What should you know? A lot. Rats are smart and relatively unhealthy animals (crappy breeding and even worse general care has done them no favours). To keep them happy, they'll need a lot of room (their cage should ideally have a plastic base with substrate to dig in and be very tall with lots of things to climb and play with). Rats are prone to breathing problems, so their substrate shouldn't be dusty or contain pine phenols - no woodchips. Shredded paper and some cat litters are better. They also shouldn't be kept in smoky rooms. As highly social animals, they also must absolutely be kept with at least one other rat (same sex, or girls with neutered boys) and given at least an hour a day of 'free roam' - time outside their cage in a safe room with lots of things to explore. They should always have fresh water and a suitable dry food mix available, and it's good to give them some fresh food each day too. They'll eat almost anything and love food that requires an extra challenge, like a boiled egg still in its shell or, when it's hot, frozen vegetables in a little bowl of water. They'll probably initially be quite timid, but if you gently let them get accustomed to you they can be really affectionate. Remember that their eyesight is terrible and they're small prey animals, so suddenly picking them up from above will probably freak them out. Instead, let them sniff you for a while and get used to climbing over your hands before scooping them up. Rats you can buy in shops are likely poorly bred, kept and handled. If you're able to go to a good breeder instead, don't give the pet shops your money when it comes to buying animals.

That about covers the basics. This forum is great, it covers absolutely everything: http://www.fancy-rats.co.uk/community/ (Sorry for ugly phone link.)