The gear is being worked on. The developers have said (though I couldn't recall when) that D3 will have more items in total than D2 did. I doubt we've even seen all the "raw" item categories yet, much less all the possible affixes those items might get.
but my main concern about the number of items is because of the ease of changing your skills the creators say that it'll be less about builds and more about gear.
We should clarify what you mean by "it" here. I'd say that your sense of unique character identity will be less about builds and more about gear, but that doesn't necessarily translate into monotonous gameplay, or everyone being the same. I actually think the flexible skill system will have the opposite effect: because you can
switch skills easily, people will do so more often, experimenting with unusual and creative skill combinations all the time. D2's unforgiving skill point system was what led to everyone using the same builds: when experimentation costs you hours of releveling, you tend to go with what's tried and tested from the start and never change it.
Once the game is well underway, I think the chances of you joining a random group and meeting someone who has the exact same gear and (current) skill & rune setup as you will be virtually zero, unless you tend to copy popular builds off forums anyway (which makes it your own doing).