Yes, I would need an optical drive and would probably need to purchase a keyboard and mouse as they will go with the old G5 tower I'll be selling.
That's going to up the overall cost of the mini quite a bit.
For sheer processing power, especially rendering video files, is there a marked difference either way ? I'm also a little concerned about graphics on the mini.
Related note: I'm actually pretty annoyed at having to sell the old tower, it's still a great machine but PowerPC is effectively redundant now.