I implemented a bitcoin blockchain parser after following along with this blog post. I havent tried changing it to work with the Ethereum blockchain but maybe it can give you some guidance. Here's a parser implemented in Go to hopefully give you some Ethereum specific examples to go off of.
The answer is patience. pyethapp is rather a proof of concept implementation than a production ready node.
I had to wait several hours until I noticed the client started to synchronize the main network. It's very slowly sync'ing for some days now and I have only the first million blocks on disk. Keep waiting for the rest.
TL;DR pyethapp works, but prepare some time if you want to work on main net.
Best Answer
I haven't used it myself, so others may want to comment further.
From the documentation,
pyethappis composed ofpythereumandpydevp2p, the former of which:So in answer to your question:
I'd say the answer is "yes".