How often are blocks produced on EOS? Are they consistent? In Bitcoin the blocks are only mined on average within 10 minutes, not guaranteed 10 minutes - does EOS differ?
Blocks on EOS are produced every 500ms (milliseconds) by Block Producers, or BPs for short (sometimes known as Witnesses or Delegates).
Unlike Bitcoin and other PoW coins, EOS uses DPoS (Delegated Proof of Stake) which allows for extremely fast and consistent blocks by scheduling them to individual BPs. They do not vary in time like Bitcoin, unless a BP misses their scheduled block.
Due to this short amount of time between blocks, BPs are required to have high quality hardware and networking, as they would need to produce and broadcast the block within 250ms (half of the block time, due to bi-directional latency in networking).
Low quality block producers would be noticed by the amount of missed blocks and would be un-voted by EOS users, thus ensuring a fast and stable network.
Blocks are produced turnwise by such called block producers within the Delegated Proof of Stake. This prevents all "miners" from rushing for the right hash like it is done in Proof Of Work. The turn duration is 0.5 seconds for EOS but may be different.
Maybe this article about DPoS helps you understanding.
Here is also a comparison between Bitcoin and other blockchains. Maybe Steem is interesting for you because they have already implemented the DPoS.
For some special cases the DPoS of EOS is upgraded to BFT:
Byzantine Fault Tolerance is added to traditional DPOS by allowing all producers to sign all blocks so long as no producer signs two blocks with the same timestamp or the same block height. Once 15 producers have signed a block the block is deemed irreversible. Any byzantine producer would have to generate cryptographic evidence of their treason by signing two blocks with the same timestamp or blockheight. Under this model a irreversible consensus should be reachable within 1 second.
Which is an extract from the Whitepaper V2.