Nowadays, we see occasionally news articles on breaking scientific news, such that most average Americans have at least heard of things like CERN, Quantum Mechanics, and the Hubble telescope.
My question is, during the scientific revolution, how much public awareness was there of the works of people like Galileo, Descartes, Huygens, and Newton? They were obviously aware of one another, with Descartes for instance referencing the works of Galileo (and subsequent backlash) as a reason for delaying publication of The World. But would, say, a carpenter in London know about the discoveries of Newton, even if he didn't understand them at all, in the way that most contemporary folks have heard of the Hubble Space telescope?
So I think there are two components to your question, which need to be distinguished:
Lets start with question 1:
The history of science generally doesn't distinguish very well between important-at-the-time, and important-from-hindsight. A lot of influential work was immediately influential, and certainly all the figures you mentioned were very influential in their own lifetime. In general academics were well-aware of other scientists, and there was a lot of international communication between them.
But sometimes we praise a scientist not because he was influential at the time, but because he was ahead of his time. Think of Mendel: his work on the inheritance of traits was completely unknown and didn't make any impact on science, until people discovered it 50 years later. Only then did it begin to have an influence. But we still call him the founder of genetics, despite the obvious fact that genetics as a research area developed independently from him and after his death.
As for question 2, it becomes a bit tricky to answer this. Also, there is an ambiguity with what part of the population we are talking about. Even today, most people will not know that the Hubble Space Telescope exists. Try going around London and ask every carpenter what they know about the Hubble Deep Field or any other question related to the Hubble Telescope - a very large percentage will not know anything about it.
So lets say we talk about the general educated public. Obviously, today more people have an education than in 1700, so the group of educated laymen would be a lot smaller in 18th century London. I'm pretty confident most intelligentsia of 18th century London will know about Newton, Descartes, Spinoza and Hobbes. We can see, for instance, that Newton was a very prominant topic in the public Boyle Lectures, which were sermons that attempted to prove Christianity and combat the atheism in England. These lectures were, to the best of my knowledge, open to anyone, like a lot of lectures in London at the time. I seriously doubt a carpenter would visit these sermons, but I have never found any indication that it was impossible for a carpenter to attend.
A second piece of evidence for Newton's popularity, is that he is frequently mentioned in 18th century poetry. The name would probably be known to anyone who had the time and interest to hear about these things. Just like how today most people will not know that the Hubble Space Telescope exists - only people with some interest in science will know about it. There's a very famous verse by Alexander Pope:
Nature and Nature’s Laws lay hid in Night: God said, “Let Newton be!” and all was light.
You can find several more examples of Newton in poetry here: http://www-history.mcs.st-and.ac.uk/HistTopics/Newton_poetry.html
However, we should be mindful that nobody except for a few brilliant minds knew much about Newton's physics. He was idolized in the same way we now idolize Einstein: most people have no clue what Einstein did, and they will think you are crazy if you explain relativity, but everyone knows Einstein was a genius. Newton was a perfect marketing success: a pious Anglican scientist had solved the biggest problems in physics and discredited the theories of the continental philosophers (Descartes, Leibniz) by inventing an elegant and all-encompassing mathematical theory of the universe. Most of his popularity among laymen was the result of religious and nationalist sentiments, combined with a healthy admiration of genius scientists.