I often have to point out that English grammar is not a settled body of dull doctrine, it's a live field of scientific investigation in which new facts are emerging all the time. So how long is it since I last learned something entirely new about the grammar of English? Oh, about… two minutes. In a press report about Al Franken's win in the Minnesota recount, I read that Franken said, "It's time that Minnesota, like every other state, has two senators." [See below for Ben Zimmer's observation that the AP report in which I read this was in fact departing, outside of the direct quotation marks, from what Franken actually said! It turns out not to matter for my purposes. The discovery in what follows is not about Franken.] That present tense on has struck me as odd. I would say It's time Minnesota had two senators. The idiom demands the preterite (simple past) tense in my variety of English. So I picked the random word sequence it's time everyone and Googled it, and I found that It's time everyone flies is a corporate motto of Cebu Airlines in the Philippines. And then, although instances of the preterite vastly outnumber cases of the present among the Google hits, I soon found it's time everyone understands and it's time everyone takes a moment on the ESPN site… It's already clear to me that people are starting to say It's time X does Y instead of It's time X did Y. That's not a major discovery; it's not especially important or interesting as far as I can yet see, because it doesn't relate to some descriptive thorny point or theoretical crux; but it's a brand new fact about English syntax that I had no inkling of when I woke up this morning.
[Added a bit later: Some of the comments below ask about why the preterite would be used, and others correctly identify the reason: the preterite tense in English is often used for what is called "modal remoteness" — it takes us away from claiming something about the actual world. If she knows where I am right now is about whether she knows in this world; if she knew where I am right now is about what it would be like in an alternate world, unlike this one, a world in which she does know. With the verb be in the first or third person you can use the special form were for this purpose (if I were you), but for all other verbs you simply use the preterite.]