I personally would have no use for electrical connections in my tank bag. But to each his own.
Same here. I know one guy who has a 12v socket splitter in his tankbag so he can charge the phone, camera batteries, and pda. Unless you're camping out in a field every night, I don't see the use. Sure, when I travel I bring along a cellphone (it's turned off when riding - who needs that kind of distraction?), and a camera, and a camcorder... but I usually charge the batteries at the hotel overnight. As for the bike, most electrical accessories are either mounted on the handlebars (GPS, Grip heaters), or under the seat (intercom).
Cheers,
Lucky