Currently, they are using cheap, plastic phones with tiny little screens and complex OSes. They aren't durable, have poor battery life and have an appalling UI. I wanted them to upgrade to an iPhone just because its easier to use than the no-name phone they are using now. However, the iPhone has way too much capability and would more than likely confuse them.
If this Nokia "dumbphone" can deliver a sturdy phone with a simple, streamlined UI I would get my parents one in a heartbeat. Pair it with a cheap phone only plan from T-Mobile or AT&T and my Christmas shopping is done this year. :)