I am an occasional user of Siri and have bought an amazon Echo Dot in order to make use of their Alexa personal assistant. In the media Alexa is frequently referred to as being an artificial intelligence. (for example Popular Science, 25 June 2015 and Forbes 14 June 2016) As with Siri I would point out that Alexa lacks the kind of value system that Asa H and some other AIs have. This limits its intelligence.
I approve of amazon's intention to slowly grow Echo/Alexa's capabilities. This makes much more sense than what some of their competitors are attempting. (e.g., Jibo) The price is also very reasonable.
The home automation apps and hardware would allow you to interface Echo with something more resembling a mobile robot if you really wanted to.