* This might be a worthy tool for simulating aspects of scale: http://imunes.net/
* I assume power usage is a non-trivial concern (looks like yall have been worried about this too). I've tried my fairshare of P2P apps on mobile, and this can be a dealbreaker for many folks. I assume this will be something that has to be dialed in on mobile clients (and probably provides options to the user). I'm sure there are many trade-offs to consider, and I'm hoping logical accounts will provide significant advantages here. Are you feeling confident this will succeed?
* The Store-and-Forward problem looks like a really big deal. Defaulting to friends (for those folks who are lucky to have them) or a chosen subset to proxy seems reasonable. Having the clear ability to pick out who we trust here (including volunteer networks) seems solid (I'm a huge fan of Retroshare's F2F concept). I take it that, ideally, with logical accounts and excellent NAT traversal (also a sore spot usually), one's own cloud of machines will obviate some of the desire to run anything in a datacenter (and even perhaps make friends a fallback). I'm excited to see Dendrite and Conduit grow!
* As part of that portability, at least to my ideal, I'd be able to join my network from scratch using a password hashing algorithm for the private key, as otherwise I may be reliant upon secondary networks to move keys. This is often one of the first applications I want to install on a system to bootstrap myself in.
* Pinecone's Topology looks like a good idea (Yggdrasil is dope too). That metadata problem may still raise its ugly head here. Do you predict the use of onion routing, at least with Tor and i2p, will be relatively easy to integrate in addition? Do you foresee Matrix enabling its own onion routing some day?
* If you had to take a wild guess at the first stable moon landing, when do you think that might occur? Do you think 5-years may be acceptable?