Is it advisable to get a recommendation letter from industry for a Masters program in Computer Science in the US? Most US colleges require three letters of recommendation from prospective Masters students. There are two professors that I have worked with extensively in my institute, and I am sure that they can give me excellent recommendation letters based on my research work with them. The only other professors who can recommend me are professors with whom I have not interacted with too much outside class, and may not be able to give me much more than a "He performed excellently in my courses" recommendation. I do not feel that they can add much to what the first two professors say, seeing that I performed well in their courses too.

I worked at a large software company as an intern and left a very favourable impression with my manager there. He has said that he would be willing to write me  strong letters detailing my teamwork, coding ability, communication skills  and ability to work with tight timelines.

I wanted to know which letter MS programs in the US would value more as a third letter - the impersonal "He is a good student" from my professor or the more personal and authentic one from my internship manager.
There is no definite answer to this question because it may depend on the judgement of the person reading the letters, and on what is actually in the letters.

But with that being said: professional experience is very different from coursework so it will most probably be beneficial to show that you can do both.