Typo on front page.
Rather than "Rather than a myriad of checkboxes..." it should be "Rather than myriad checkboxes..."
Rather than "Rather than a myriad of checkboxes..." it should be "Rather than myriad checkboxes..."
> Usage Note: Throughout most of its history in English myriad was used as a noun, as in a myriad of reasons. In the 1800s, it began to be used in poetry as an adjective, as in myriad dreams. Both usages in English are acceptable, as in Samuel Taylor Coleridge's "Myriad myriads of lives." This poetic, adjectival use became so well entrenched generally that many people came to consider it as the only correct use. In fact, however, both uses are acceptable today.
People that contribute to thefreedictionary.com, evidently.
A quick Google Ngram search supports the claims from thefreedictionary, that "a myriad" or "myriads" was used first and that "myriad" as an adjective was only used later: https://books.google.com/ngrams/graph?content=%28myriad_NOUN...
It looks like "myriad of" has been correct in the past and is still used widely.
http://www.oed.com/view/Entry/124538
http://www.oed.com/oed2/00154839;jsessionid=AC4DB817EFBADA5F...
I have had similar experiences, though, where I was convinced that some word or phrase usage was just incorrect, and where it turned out that I had just not happened across it. Fortunately, a minute of research can today fix any such misconceptions!
Whether I'm correct to feel like this is left as an exercise to the reader.