Engineering excellence and user generated content (UGC) have propelled YouTube to Facebook-level reach, with growing viewing in all demographics and on the TV-set

However, the commercial limits and PR risk of its long-tail content model have prompted a diversification effort involving subscriptions and long-form content

Becoming a major part of Google’s revenue amid fierce OTT competition would require YouTube to be more flexible in its partnerships with the AV industry, and a more aggressive go-to-market strategy

Even with the decline in linear television viewing, online video remains a small component of total video consumption. The growth area is unsurprisingly SVOD; subscription video now makes up about two thirds of the UK's digital video spend.

Netflix is moving from an aggregator of content to a "channel" in its own right, increasing proportionate spend on original programming, something that the public service broadcasters are unable to do for differing reasons. Amazon had a tough 2017 for video, and are still struggling to create a hit.

New Nielsen audience data suggests that the long-term "library value" of Netflix's originals may be overstated, while the BBC's iPlayer continues to be hampered by not really having a library at all.