I'm already ITIL v3 foundations certified and I'm thinking of going to the next level of certification, which is the intermediate level if I understand the scheme correctly.
First, I seem to recall hearing ITIL certifications are good for life, correct? Or at least good until v4 comes out.

Second, in order for me to actually become a certified intermediate level person, do I have to complete all modules within, say, Lifecycle or Capability streams? Or can I just pass a couple of the modules that interest me and that will be sufficient to gain intermediate level certification?
Third, what are the specific course/test numbers I would need to take? They don't seem to list it anywhere on the official site.