I thought it was no limit besides the 10 minute per block rate.
Also I know the difficulty changes with the network hash rate (which would put the blocks under or over 10 minutes) but I think the block reward (currently: 0.149218 BTB) decreases with time.
Can any of the developers confirm this?
There's no absolute upper limit on the money supply. It's the same with PPCoin, Novacoin, Yacoin (all based on the same source code). Sunny is the developer of the PPCoin code on which bitbar and those others are based on. It's just a case of the more popular it gets, the smaller the block reward becomes.
We can still make predictions though
static const int64 MIN_TX_FEE = CENT/100;
static const int64 MIN_RELAY_TX_FEE = CENT/100;
static const int64 MAX_MONEY = 500000 * COIN;
500 000 COIN or am i wrong?
The same code is in PPCOIN, but ppcoin has 2,000,000,000 max?
correct
Why does everything say that PPcoin has no limit then?
From the PPcoin thread:
Unlike bitcoin, ppcoin does not have a fixed money supply cap. However this does not mean that ppcoin is significantly more inflationary than Bitcoin. The minting design attempts to better mimick gold than Bitcoin does in our opinion. Gold does not have a known money supply cap either, but we know it's reliably scarce. For many years annual inflation of gold is around 1-3%. In ppcoin there are two types of minting, proof-of-work and proof-of-stake. The proof-of-work minting rate is regulated by Moore's Law, which dictates that our ability in proof-of-work grows exponentially. We are aware that Moore's Law eventually has to end, but by that time inflation in ppcoin is likely already approaching gold's level. The proof-of-stake minting introduces at most 1% annual inflation. Meanwhile ppcoin's transaction fees are destroyed to counterbalance these inflationary forces. So overall ppcoin's minting design is still a very low future-inflation design comparable to Bitcoin.
There is a 2-billion coin max value in the source code, however that is only used for consistency checking and is not meant to be part of the minting design.
Since 0.2 release a 'moneysupply' stat is included in the getinfo output so everyone can see how many coins are in the market.