1. It's a PITA -- we'd need to drop out of synchronising, and finish the job safely. This isn't that easy, so it's always been a low priority. It won't make it into v2.0 final.
2. So would I, but then people would know how slow the protocol really is
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. I started hacking on it a while ago (you might notice the "Estimating Transfer Size" item appear in the sync dialog in the next beta. However, there's still quite a lot of work to be done to it. It probably won't make it into v2.0 final.
No, the Rio Riot will not use emplode.