Why is the Xbox 360 called the Xbox 360?

BTW, For anyone looking for a great pair of head phones for working out or running, these have proven to be fantastic for me:

Sennheiser PMX80 Sport Series II Behind the Head Ear Phones

And the Sennheiser CX380 Sport Series II Noise Isolating Earphones

Hope it helps.

Good deal for a well reviewed set of behind the ear headphones.