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Should the words “internet” and “web” be capitalized?
For the most part Internet is capitalized, less frequently it occurs uncapitalized. Is this a style issue or is one considered more correct.
Subjectively, would the average reader consider using the uncapitalized version to be a mistake / display of poor English?
Internet should be capitalised, because it's a proper noun and defines a single, definite thing not something general (like the word tree, for example).
If you look up the word, you'll find it always capitalised, I can link you to the OALD, as an example.
If you're writing in some informal context, most people won't mind if you write it lowercase, though. But if we consider some official context, for example writing your Curriculum Vitae, you would write it properly.
EDIT: After Garet's comment, I decided to introduce a distinction. If you want to refer to a general inter-network (which by the way, it's the compound where "Internet" comes from) or if you want to use the same term to refer to something which is not the World Wide Internet, then it would be written lowercase.
An internet is simply a network of networks. The Internet is the worldwide TCP/IP-based internet that we all share.
Usually, you'll want to avoid the generic lowercase usage, to avoid confusion.
I would say that it is becoming less and less common to write "Internet", as if it were a proper noun. Indeed, the use of the phrasing "the internet" tends to indicate that "internet" is not a proper noun, because if it were, the word "the" would be redundant.
The proportion of people who are familiar with the origin of "the internet" as a proper noun, or indeed to who understand that the phenomenological features of the internet qualify it as being capable of having a proper noun, seems to be dwindling. My guess is that most people think of the internet as being like the telephone system or the air - a thing that lacks either unity, number, or identity.
