Before heading into market cap pass / no pass discussion you might want to consider whether those two coins are really in the same race. Bitcoin was created solely as digital currency, while Ethereum is technically anything but currency (yes, even though it's tradable).

So :

1. Will ETH pass Bitcoin as digital currency in broad usage? Most probably not.
2. Will ETH pass Bitcoins market cap "as platform"? Given it's corporate support, that is highly probable. Big companies simply have more buying power than common folk.

One day, ETH might have higher value than BTC but it doesn't mean it will be as useful or as widely adopted in daily usage as BTC.