Let's do this again:
"The market cap of PPCoin is worth millions of dollars. If it was easy or trivial to attack and do double spends or whatever, why isn't it happening?
That's not a rhetorical question, I am genuinely interested in your reasoning."
You cannot attack "a market cap" with double-spend, you have to attack a concrete business, an exchange, for example.
Guess what, people aren't really eager to rob an exchange... Also, it isn't as lucrative as it seems. (You're limited to whatever liquidity is currently in orderbook, basically.)
Also it might be easier once Sunny removes centralized timestamping.
I'm guessing since you ignored this entirely, you've realised how foolish the entire premise of your argument sounds.
In that topic you linked to, the guy is using 0.2 not 0.3 and in the 0.3 release Sunny said it contains bug fixes. I don't see any reports of this happening with 0.3, please link me to them if you do.
Idiot, I've just read source code, and I understand how it works. You don't.
Checkpointing is necessary for security.
Which, again, shows that you have no fucking idea about what is proof-of-stake and how cryptocurrencies work.
Please stop trolling.