What is the incentive structure for nodes running Lightning / Raiden?

[madhavanmalolan]

What are the economic incentives for the participants who run a Lightning node?

I am aware that there are over a 1000 nodes at this point, will this hold even after the novelty dies down?

What is in it for the people who maintain such huge (?) nodes, and locking up their own funds?

[HeRetiK]

Being able to send and receive transactions over Lightning Network, thus saving on-chain transaction fees.

You also receive transaction fees for routing Lightning transactions, however those are likely going to be negligible and therefore probably won't be much of a factor.