My family has always been quick to embrace new technology. When my oldest sister went off to college in the early mid-70s, her university was unusual in that it had a computing center and apparently (I was a wee lad at the time) encouraged education in computing. When I was slightly less wee, my middle school offered a computing class. We learned to make flow charts and to program in BASIC. Once we'd written our little programs, we would head over to the teletype machine in the closet in the back of the room, dial up the county mainframe, and if all went well, find out if our programs worked.
Around that time, my folks bought a computer. I think the first one was an Apple II +, which was roughly shaped like a flattened typewriter on which you could perch a TV. My parents took computer programming classes at the local community college, and we used the computer to play with programming, and even to do some very basic word processing. (For you young folks, the word processors were characters and markup---there was no WYSIWYG.)
Then the Macintosh came out. It was beautiful. And my parents got me one as a graduation present. Always ahead of the curve, they were (and still are, mostly). My computer served me and many others through my years in Ann Arbor. During my time there, typed papers faded away, and computing centers (filled with Macs) opened up in central campus locations. And one day, while sitting at one of those computing centers with a friend, I was told I could write a letter to a friend of ours overseas---on the computer. It was called "electronic mail", and it was instantaneous, and no, it didn't cost anything. Remarkable. Of course our email addresses at the time were rather different as I recall.
This was an exciting time. In high school we had learned how to use libraries to our advantage, searching card catalogs, reference indexes, and huge books full of citation indexes. When I got to college, we continued with this system, with a little help form computer terminals that could help us find the huge books that helped us find smaller books and articles. By the end of college, I'm not sure anyone used a card catalog or any of the heavy tomes, or even knew where they were.
All of that seems rather quaint now. I can sit here at my computer and search for articles about, for example, direct current cardioversion, or murine models of MDMA tolerance. Often enough, I can find the full text with citations, and the citations themselves are linked to their sources.
The technical aspects of science blogging aside, I don't think we could have had science blogs twenty years ago. There was no way to get up to date information on discoveries, no way to quickly find references, no way to produce a well-referenced post on breaking science news. Writing a blog post without modern information science would be more like writing a term paper. And who wants to read a blog that's only updated a couple of times a year?