The Google Predictor API V1.2 is out! “The Prediction API provides pattern-matching and machine learning capabilities. Given a set of data examples to train against, you can create applications that can perform the following tasks:

• Given a user’s past viewing habits, predict what other movies or products a user might like.
• Categorize emails as spam or non-spam.
• Analyze posted comments about your product to determine whether they have a positive or negative tone.
• Guess how much a user might spend on a given day, given his spending history.

" [see more] There are libraries and sample code for Bash, Java, .Net, Python, Ruby, … For details of samples look at guide Links:

• Ford & Google predictor (also here)
• Ford & Google Trends

As alternative, for Long Term Prediction over Time Series, you can have a look at Strategico.