You know what, it's proving quite hard to find a single review from way back when, be it positive or negative, lol... so I guess you've got me there!
Anyway, here's a rough translation of what my english lit book says about it, if you care:
Like The Grapes Of Wrath, Brave New World, Catcher In The Rye or Lord Of The Flies before it, Atlas Shrugged's initial reception was disastrous. The book was a hit, but just like it's mentioned peers it was mostly rejected as deviant due to the sensitivity (not sure if this is a thing in english, but I'll go with it, lol) of it's subject matter. Rand's style and story telling were well received (personally, I think her writing sucks, but I do agree she is a good story teller) but the book as a whole was mostly rejected by the critics as an ungodly abomination.
The author then procedes to explain (over several paragraphs which I obviously won't translate) how, because of it's persistant popularity, Atlas actually came to be regarded as a modern American classic, although it struggled (ahah!) to find an audience overseas. The modern consensus is that it's a very important piece of fiction in modern english lit and that it is a cherished work by the literary community.
And quoting again: Except, ironically, in it's homeland, where the intense hatred it still provokes can only be matched by the love it's enthusiastic supporters have for it. There, it remains an equally influential, controversial and divise work, much like Rand herself.
I'm not an english lit major, but my flatmate is, and he goes to the same faculty as me so I end up going to alot of lectures because of that, last week they were actually discussing this (late 50s) and when the teacher mentioned Atlas Shrugged as a modern classic, some guy started talking about Bioshock and everything got a bit derailed so he ended up talking about Ayn Rand for a bit longer and said what I'm now regurgitating here. It was why I decided to read it again, even.
I'm sorry to sound rude, but I'll take the word of a Welsh english lit doctorate (and the book I just quoted from) on this subject over someone who's probably from the US.