Is this 1626 words dictionary enough now or should we go with a bigger one, also to allow less words?
Why?
If crypto.getRandomValues is working properly then 1626 is just perfect. If crypto.getRandomValues isn't working then even 20,000 words won't be enough, as real entropy will be limited by the random number generator.
Some people are having difficulty comprehending that 128-bit is a very big number.
Lets assume the worst case.
Lets say in two years, 1 billion people are using wesleh'sy client and everyone created their pass phrase using these randomly generated words.
Now lets assume that every bitcoin miner in the world (millions of dollars of electricity per day) all work together to find just one of these 1 billion randomly generated pass phrase. The current hash rate on bitcoin network is 3 million GH/s.
How long would it take for the entire bitcoin network combined to find just one of 1 billion pass phrase?
Total number (aprox 128-bit) 1626^12 = 3.4×10^38
1 billion users, 3.4×10^38 / 1000000000 = 3.4 x 10^29
Now the entire bitcoin network combined works to find just one pass phrase 3.4 x 10^29 / 300000000000000000 = 1133333333333 seconds
that's 36,000 years (36 thousand years).
lets assume they get very lucky and find one pass phrase only after 1% of search, that's still 3 thousand years
And after all that work (and electricity) and 3 thousand years later, they might discover that the account they did find only had 2 Nxt in it.
The point is that the problem (if there is) will be with random number generator -- not with number of words, which are just fine.
That's why I keep saying you don't need 50 or 100 character password (not even 35, actually -- 25 is fine). . It doesn't add any more security. If there is a security hole (like for example keyloggers) even 1 million character password isn't going to help.
You're right, bitcoinpaul was only suggesting that, from the end user point of view, a 10 words passphrase is a little more convenient than a 12 words one. This is possible with a larger dictionary.
That will require about 7200 words. That's 4.4 times more words. wesleyh will have to find a lot more words that are still simple every day words.
) are welcome! 
