There's a lot of things you can discuss. You can discuss stuff regarding the Pokemon anime episodes (Thoughts, opinions), top 5 lists, TCG strategy reports and, when the game comes out, possible updates on online leagues for Pokemon D/P.
Its just a matter of having a firm schedule and deciding on what the topics in question will be during that week. I've done a few trial attempts at podcasts with a Digimon podcast, but we always have technical difficulties. As long as you have the right equipment and plan in advance, you should be fine.