[Barry_Black]

1. I believe it's possible to manually choose what network the device is on....EDGE or GPRS..

2. Is this feature available by device or the service the device is on?

[John Clark]

You can choose which network, sometimes. What service that network provides, either EDGE or GPRS, you don't get to choose. it's just whatever they have in your area.

[Barry_Black]

What determines if you can choose the network? Device?

[John Clark]

Network/carrier and calling plan.

[takeshi]

If you're Cingular Orange you can't choose unless roaming internationally and (IIRC) properly provisioned.