According to various on-line updates, apple will have 50%+ margin on the iPhone. One site is
http://www.pcmag.com/article2/0,1895,2085350,00.asp.
Cingular on the other hand will get you for two years, probably with a contract of at least $39.99 plan or even higher since you will want data plan, full internet access, etc. So 24 months @ say $60/month and they generate close to $1500.
Not bad, we get to fork over $2000 over two yr period to be the first on the block with the iPhone