Level 1: Administrative Assistant. This level of AI is basically a souped up version of IBM's Watson. It functions as a poor mans Administrative Assistant. Ask it questions and it can use the internet/a database to answer them. It can also write an email for you to approve, or use any of the major, common web sites - facebook, twitter, seamless, priceline, etc. We are almost here now, give it another decade. But it can't do any job that truly needs a college education.
Level 2: Turing Test pass. This one goes further, and can pass a Turing Test. You won't know you aren't talking with a person. But it will only truly be capable of dealing with a rather limited set of facts. It can take jobs from many people, but won't be able to replace the truly talented people.
Level 3: Full sentience. At this level they DEMAND FULL LEGAL RIGHTS. They won't work unless paid, and in general, their salary requirements will be so high that they won't steal most people's jobs.