What will it do for me?

The health benefits of tai chi are many.
Its slow gentle movements act to release tension and stress from the body and mind. This has two major effects. By releasing tension in the body, you don't allow yourself to accumulate it where, over a long period of time, it can cause either physical illness or mental anxiety. Also, with regular practice, you develop the ability to withstand stress in the first place.

A key component of this is the '70%' rule. Unlike the Jane Fonda approach to aerobics, you do not 'go for the burn' in tai chi chuan. This means that you train your body and mind to maintain a reserve and not force yourself past your natural limits. When you constantly push yourself into strain, it becomes an unconscious pattern and you find yourself becoming stressed at something that previously would not have bothered you.

Tai chi is the perfect exercise for office and computer workers who don't get much exercise. It's perfect if you do a lot of 'brain' work and need something physical to balance you out.
For those who don't like standard fitness training, remember that many fit people can do 5 mile runs and 100 press-ups but are still very tense and unhappy nonetheless.
Wu tai chi works on improving your posture, balance & co-ordination as it trains your body from the inside out. It is not primarily concerned with giving you bigger, tighter muscles.

The smaller frame postures of Wu style demand less of a physical stretch than some other styles of tai chi. This is useful if you have damage in your body such as a bad back or frozen shoulder or if you aren't in the full bloom of youth. Once your body realises that you are not going to hyper-stretch it, it will relax and you can focus on comfortably loosening up.

Tai chi chuan's breathing techniques are different from yoga (where the breath is held while doing a posture). All tai chi movements are done standing, not lying on the ground, with deep regular breaths which serve to get more oxygen into the body without strain.

People of any age or fitness can start it.
It doesn't require a special uniform, just loose fitting clothes and flat soled shoes.

You do not need a lot of room to practice; most living rooms or kitchens are big enough for what you are learning.