It does not enhance (in terms of monetary properties), nor scale, the bitcoin blockchain. Furthermore, its arrival puts into stark contrast the monetary properties of a natively scaleable, natively fungible, publicly transparent blockchain vs a paralysed one that is none of those things and requires a proprietary, corporately owned and run external infrastructure that trades trusted-party promissory notes in place of bearer tokens.
Consider the alternative: Offchain transactions with cryptsy-like payment IDs on third-party platforms.
Compared to that, payment channels are a decentralized paradise. It does help scaling if it aggregates payments into less bloat. And it will also allow small micropayments that at some point may be infeasible as ordinary txs.
The creation of payment channels will be a function supported by the protocol. As such theoretically anyone with the knowhow could make such channels. I recently read there are 4 implementations in the works by different parties. So there is nothing inherently corporate or privately-controlled to that. For example the DASH masternodes could be used, say, for providing payment channels for bitcoin.