The rumors were all true! Steam’s Summer Sale, which was rumored to be beginning on June 23, has in fact begun on June 23, and it will be continuing all the way through July 4. Officially called the Summer Picnic Sale, the new sale appears to be taking on from the previous one, where it just puts all the deals available for the customer upfront, with no daily or flash deals offering timebound discounts.
So far, there also does not seem to be any metagame associated with the sale, though it is possible that it is just well hidden, and that someone or the other will discover it eventually. That said, at least there seem to be new trading cards that are being offered simply for browsing your discovery queue, so that’s something.
As of right now, Steam seems to be very slow or just down outright, owing to the sheer number of people who are probably trying to access the storefront right now. But since there aren’t any timed deals anymore, you don’t have to worry about missing a good deal on a game you wanted, at least.