For $30 plus tax, you get 40 Genesis games, and 9 unlockables.  In this collection are some of the noted series by Sega for the Genesis, Master System, and the arcade (Master and arcade are unlockable).  Here is the info for both the 360 and PS3 versions:

http://www.vgchartz.com/games/game.php?id=29683&region=All

http://www.vgchartz.com/games/game.php?id=29684&region=All

I don't want to get into the details of all the games, so please review the list.  I will say just about every genre is here, except for fighting games (Street Fighter family, but side scrolling brawlers are here in spades), driving games, and gun games.  Noted series include, Phantasy Star (1-4, YES the Master version is unlockable), and Streets of Rage.  There is the Genesis Shining series also (Both Shining Force and Shining in the Darkness).  Also, Golden Axe and the Zelda Golden Axe clone is in there also (second Master Systems title in the mix, along with the original Phantasy Star.

The unlockable games (all 9) are not too hard to unlock.  The required plays to unlock seem a bit unusual.  What Flicky has to do with Fantasy Zone, and Decap Attack has to do with Zaxxon remains a mystery.

The graphics upgrade works on a bunch of games, but some you do need to tweak.  You do have the capability of doing 4:3 or 16:9 ratio, or stretch your own.  You can turn smoothing on and off (this is a big plus, because some games smoothing makes things worse).

No play over XBox Live, but there is play on the platform.  Actually, Sonic II, beating the first boss with a second controller plugged in (2 players) is how you unlock Phantasy Star.

All and all, I have to say this is how companies need to do retro.  The unlockable games are not hard to get to (oh Flicky, you are hard.  Why be so hard to deny me Fantasy Zone?).  There are the usual interviews and so on.  And the package is an upgrade over the prior Genesis collections, and worth getting, even if you have it.  And the games do remind you that 16bit fun is still fun.  Oh yes, and how much the Genesis version mangled Altered Beast (the arcade version is unlockable).  And also how good the original Streets of Rage's music still sounds today, and how its play on the Golden Axe formula for a Double Dragon game is a fresh take now.

and i have even more running on a emulator for free. That being said it is good for people without a pc

planning on picking it up

You get bonus goodies with it, achievements and trophies, plus you get to legally get copies of the games.  The package does look to upscale the images, and also lets you adjust the size of your screen appropriately.

I picked this up for ps3 today, good time :)

is it updated with HD visuals, or atleast scaled?

The best part of this game is the pre-order bonus in Australia: The soundtrack on VINYL!!!!

Upscaled to 720P.  You can also adjust the screen to fit your monitor (I have a 15x10 monitor for my videogame systems, so I don't get 16x10).  You then can add smoothing to it, to round out the rough edges and jaggies on the sprites.  This, however, makes the text look more blurry.  There are some games, like Sonic, where this makes everything look real good even today.

I would like to see Sega come out with a Volume 2, and get Gunstar Heroes, and hopefully Herzog Zwei in there.

Ya, is it scaled?

Cuz, retro games look like ass on HDTVs.