Only in the sense of "brought to the USA". Megabus has been going longer in the UK - 10th anniversary this year, I believe.

The concept has changed over time, it started with normal double-decker buses as a super-low-cost bus service, but has progressively upgraded. A bit like the evolution of easyJet, really, which started as a rock-bottom cheap operator competing with Ryanair (Europe's equivalent of Spirit) and ended up applying demand pricing and chargeable food service to a more upmarket segment than it started with.

Interestingly, Stelios tried the concept as well using minibuses as easyBus. This is still around operating airport services, but was a massive flop by comparison, perhaps surprisingly.

Neil