Here is the source still unconfirmed though but it sounds possible:
http://kotaku.com/5909109/gamestop-admits-defeat-starts-selling-steam-vouchers

personally I hope it happens because I don't like using my debit card that much to me it's just easier to use a voucher.

cool, i guess. useless to me, though. i'll never set foot in another GameStop store again, and i use PayPal for my Steam purchases. hasn't failed me yet.

I wonder how long before origin gets their own voucher, and hopefully here in gog aswell :)

After the fiasco I've had with their download service I'm not surprised, spent all weekend emailing Stardock (Gamestops support was useless) to get the games I paid for back so I could actually use them. I was given the were not trained on the PC digital side excuse from GameStop phone support to being flat out treated like an idiot.. I have to give Stardock points even though they do not own Impulse any longer they took care of me. But I am out a copy of Red Alert 3 that now no longer appears in My Games, I guess they showed me :-).

Stores already sell "Store credit" on XBL and PSN as well as other kinds of vouchers so i wouldn't be surprised if this was true

Will be a nice option for those without credit cards/ those that don't like to use them online that much.

got an update: apparently it's going on sale at may 15:

http://www.joystiq.com/2012/05/10/report-gamestop-to-start-selling-steam-vouchers-next-week/

'edited' (never mind apparently the kotaku source already said that I miss read and I apoligize)

Oh mah gawd yes.

I CAN CREATE MORE TF2 IDLING ACCOUNTS WOOHOO :P

This is actually a pretty good thing for me, I won't have to deal with PayPal's BS. Now if only EA Origin let me do this too.

Why not? I doubt many GS customers have any interest in Impulse anyway, so a deal with Steam makes perfect sense.

Wouldn't surprise me, other places have them. I really don't like using a credit or debit card online much, usually I'm using prepaid cards anyways.

Considering how zeaous some people are with wanting Steam, its a smart move on GS part.

Awesome I've always wanted something similar to XBLA and PSN pre-paid cards for Steam.