Am I missing something? Most of the decks I've created so far, I think are standard legal, but it doesn't say that anywhere, but when I look at "Top Decks," etc., it will show the format of the deck?

I was looking forward to using this site, to help me potentially make Standard legal decks using some of my collection of Revised edition cards and the like. Can I search my Inventory, for instance, for Standard legal cards only, for instance?

So my understanding is that this exact functionality is being revised/repaired as the addition of BNG in addition to the changes in the bannings for modern have caused a few cards to be in flux.

That being said, you can look at your inventory for anything that's standard legal by using the "editions printed in" filter and selecting everything from Return to Ravnica up to Born of the Gods... it SHOULD pick up all your older stuff that's been reprinted in the latter sets.

Excellent. That would explain it, thanks!

I know it is a known issue but is there any update on the fix for this, to show what format your deck is?

This will be fixed in a couple of hours.