This isn't exactly correct. The development of the means of production is simply one part of capitalist competition, and also does not necessarily lead to "workers being forced out of occupation." The means of production is part of what Marx termed constant capital (as opposed to labour-power, which is variable capital - see this link for more information on constant and variable capital). The real source of surplus value is in variable capital - the exploitation of labour.and I just noticed it right before I read your post. I believe that according to Marxist theory, the cannibalization of capitalism with happen softly.. the workers being forced out of occupation by technology, and the cognitive premise to commune as they did in the factories (experience has pressed the subconsciousness of unity amongst the workers, as each worker is an "appendage of the machine").
This exploitation can take many forms: cutting wages and/or benefits, increasing the length of the working day, making workers work harder/faster so that their wage is actually worth less in comparison to the amount of goods they produced, etc... So while the means of production are increased, the working day can also increase.
"Is it not a real contradiction that the means for reducing physical labour, such as mechanical and other improvements and betterments, are transformed by it into means for lengthening the working day?"
-N. Sieber, "Some Remarks on the Article of Mr. Y. Zhukovsky 'Karl Marx and His Book on Capital'" (Otechestvenniye Zapiski, November 1877, p.6)
If you're interested in learning more about Marx's economics I highly suggest you read Marx's Kapital for Beginners. It is one of those introductory books that's written in cartoon format. I have transcribed it here, although if you read it there you won't get the impact of the cartoons. However, that's probably the best introduction to Marxist economics that I've ever found (aside from perhaps Mandel's book, which is considerably longer), and is very easy to read and not that long (I think it took me a night or two to read it).
And what do you mean when you say that it will happen "softly"?