Twitter is abuzz with speculation regarding exactly which device(s) will be given to the lucky Google I/O attendees. One twitterer claims to have it on good authority from a Googler that our beloved Google will be giving away not one, but two devices to those at the Moscone Center.

One of the devices will be a tablet, though no specifics on which tablet was announced. If I were a betting man, I’d put money on the newly released ASUS EeePad Transformer, though Motorola’s Xoom tablet is also a strong possibility.

The other device will be a Nexus S phone, though no word on whether this will be the T-Mobile-friendly Nexus S or the newly-released Nexus S 4G on the Sprint network.

Now, we must stress that this is strictly a rumor, and we won’t know for sure what will be given away until tomorrow. That being said, we love speculation, so what do you think Google will be giving away after tomorrow morning’s keynote?