Differential pricing for video calling – is this a disability issue?

A few days back a conversation on Jaiku in which a comment was made regarding the use by the deaf as a potential driver for video calling.

My thoughts on this are yet to be fully formed but it raised a couple of immediate questions;

1) Does 2-way video calling potential level the telecoms playing field for those with a hearing impairment in that now that can use the service to lip-read (assuming they can)?

2) Has anyone done any research into this?

3) Does the differential pricing for video calls, whereby the operator’s charge more for a video call than a voice call, represent discrimination against those unable to utilise the voice service?

Rather obviously for the deaf SMS, IM and microblogging services are a level playing field already.

Hmmm. This needs more thinking.