Is there an algorithm that extracts meaningful tags of english text

Question

I would like to extract a reduced collection of "meaningful" tags (10 max) out of an english text of any size.

http://tagcrowd.com/ is quite interesting but the algorithm seems very basic (just word counting)

Is there any other existing algorithm to do this?

Answer 1

There are existing web services for this. Two Three examples:

• Yahoo's Term Extraction API
• Topicalizer
• OpenCalais