So, what actually happens on June 7?
On June 7, there will be a few downloads available. The first is a title update/patch. This will be automatically downloaded to your console of choice when you are connected to the network. This patch is basically an under-the-hood primer for the other two downloads, and doesn't have any real visible functionality.
The second download is a free "Update Kit". If you're not planning on buying Arcade Edition, you're going to want/need to download this for matchmaking and spectating purposes. However, you'll still be playing Original SSFIV.
The third download is the Arcade Edition DLC (1200 MSP/$14.99). This is a required download if, you know, you want to play AE.
I don't own a copy of SSFIV. Can I just download the Arcade Edition DLC by itself?
Nope, it's an add-on, so you need a copy of Original SSFIV in order for it to work. But luckily, we have a boxed version that you'll be able to purchase on June 28 for $39.99! So if you haven't had a chance to play much SSFIV, this would be a great time to start.
When is the dadgum PC version coming out?!
Trust me, nobody wants to get the PC version out as soon as possible more than us. We still have some logistical hoops to jump through before we can set a hard and firm date, but the goal is to definitely be in the earlier part of July. Scout's honor!
Will the PC version have the ability to toggle to Original Mode?
Technically, yes, though it's much less relevant for the PC version, as Original SSFIV wasn't released. (And to clarify, the the PC version of AE will not be compatible with the PC version of SFIV, same as the consoles.)