What are the arguments for and against using the Lightning Network with Bitcoin? In addition to the question in the title, when will Lightning Network go online, or, if there isn't a proposed date yet, what is a ballpark indication of when it might go online?
pros: 


Lower Transactions Fees
More Transactions per second / block possible
micropayments possible
payments are more private than on bitcoin


cons:


funds are on a hot wallet
(at least currently) node needs to be online all the time
still somewhat buggy
(at least currently) only small amounts can be routed