Rooibos, is usually red, and aromatic. It is often celebrated for its "super" antioxidant properties. It is known to be a natural friend to the immune system, and contributes to one's health. Antioxidants, are great at fighting free radicals (often held responsible for aging, or premature aging). Rooibos is known to be a good "complexion calmer".
It is slightly sweet, and sometimes nutty and has a hint of earthiness to it. In general, its probably not a good idea to use this tea if you are pregnant or lactating. Always consult your doctor first.
When making rooibos tea, you can make it the same way you would a black tea, and you need not worry about it getting bitter if steeped too long. You can sweeten the tea with honey or sugar, or use lemon, etc. There are many great teas out there adding other things to it like pomegranate, orange, chamomile, etc.
Rooibos also contains a number of phenolic compounds, including flavanols, flavones, flavanones, and dihydrochalcones, and lacks caffeine, which are more beneficial traits. Rooibos is purported to help with things like nervous tension, digestive problems, and allergies. Some of the more traditional uses for rooibos in South Africa have included alleviating colic in infants, allergies, asthma and dermatological problems.
So far, there seem to be no adverse effects of rooibos, another definite plus.