This isn't a big deal in terms of most apps since they were designed for use with regular phones or tablets, but this is huge for emulation. The only downside to using NESoid and SNESoid on my phone is that the controls suck. Having a portable system that i could play emulated games on using a real controller is rather attractive. On the downside if i remember correctly the USB ports for the Transformer are part of the keyboard attachment, so it sounds like you can't use the controllers without also plugging in the keyboard, which detracts from the portability and convenience slightly. But i'm not seriously considering getting a tablet until Android Ice Cream comes out, so perhaps by then Asus will have released a Transformer 2 that fixes that problem?
On a side note, Sony and Nintendo really need to work on supporting their controllers for PC gaming. Sony's controller already uses a USB connection but there's no first party driver support for it. I managed to get mine working with a little work using third party drivers but it took some work. The Wii controllers don't even use a USB port. Maybe that's something they'll fix with the Cafe? There's no obvious direct benefit to them from encouraging this (at least i expect the profit they would make on selling extra controllers would be pretty minor) but i think it has a big impact on the mindset of gamers. All the indie PC games i've tried recently that have controller support assume that you're using an XBox controller, because a lot of PC gamers also own consoles and that's the only console controller that works easily with PCs. And if you spend hours playing games on a PC using the XBox controller i've got to think that's going to ingrain certain habits and impressions in your mind.
