Which games are good, and should I consider buying?
eeeee it starts tomorrow
What timezone is Steam on?
There's no proof that the sale starts tomorrow, and the ad he posted was from a few years ago. The sales from the last 2 years started on the last Thursday of June.
It's on the Thursday because that's probably when the 300th TF2 update comes out, and in that update they can also add the probable summer items.