We finally found a card that can put the PCIe slot to good use. Creative labs already has its Creative Sound Blaster X-Fi Xtreme Audio 7.1 Sound Card - OEM (PCI-Express) (30SB082000000) available, and you can buy one at Overclockers for £30.54 inc VAT.
We checked here in Germany / Austrian market and we found that the same card is available, in stock, in the local store for €59.30 if you want the retail card; or €38.84 for one in bulk quantity.
We will try to get our hands on this card soon and this is one of the first Creative affordable cards to have the Optical in and out.
You can order one in Austria here and in Overclockers U.K. here. The bulk card listed in Germany can be purchased here.