Хм, забавная концепция ...
- похоже, EmoneyRu не так уж и преувеличивал насчёт "толпиться" про эту ветку 
(это я про "много букв")Сохраняется ли ip сервера или пользователя в блокчейне? - нет, более, того, предпринимаются усилия, чтобы IP было трудно вычислить, цитирую сегодняшнее "что нового в версии 0.7.3"
Privacy related change: Before this release, newly generated blocks
and new transactions were broadcasted to peers twice. This could allow
your peers to deduce that your node was the generator of the block or
transaction in question. This is now fixed. Note that somebody with
the ability to monitor all your internet traffic will still be able to
tell that it was you who generated a block, because the generating node
sends the block before having received it from any other peer. I don't
see a physically possible way to avoid that, yet. Also note that the
transaction re-broadcasting feature will continue to re-broadcast your
transactions until they are received back from at least one other node,
but will not do that with transactions received from other nodes. This
could still be used to deduce that your node was the source of a
transaction, in case the initial attempt to send it failed, and it was
re-broadcasted (but somebody already observed the failed first attempt).
and new transactions were broadcasted to peers twice. This could allow
your peers to deduce that your node was the generator of the block or
transaction in question. This is now fixed. Note that somebody with
the ability to monitor all your internet traffic will still be able to
tell that it was you who generated a block, because the generating node
sends the block before having received it from any other peer. I don't
see a physically possible way to avoid that, yet. Also note that the
transaction re-broadcasting feature will continue to re-broadcast your
transactions until they are received back from at least one other node,
but will not do that with transactions received from other nodes. This
could still be used to deduce that your node was the source of a
transaction, in case the initial attempt to send it failed, and it was
re-broadcasted (but somebody already observed the failed first attempt).
Сколько в блокчейне транзакций? - в каждом блоке сейчас 255 транзакций, между блоками 1-2 минуты; сейчас блокчейн весит 130 Мб (он находится в СУБД H2);
Приложения грузят в блокчейн свою инфу, есть лимит на загрузку? - лимит есть денежный: 1NXT/1000байт, ну и не более 255 * 1000 байт за один блок;
Объем блокчейна бесконечен? - нет, он будет "чиститься" раз в год, будут удаляться ненужные транзакции; старые Arbitrary Messages, т.е., грубо говоря, ежегодно будет создаваться новый Генезис Блок (за 1440 блоков от нового года). Полный блокчейн будет сохраняться у Сервис Провайдеров (да, он будет бесконечен).
