With recent surge in Ethereum and ICO's being all the rage every one expected Ethereum to overtake Bitcoin in terms of market capital. What people should do is understand the technology and how ethereum works before investing in it.
Ethereum blockchain is quite new and not that big if we ignore the recent flurry of activity. It does have the scaling problem that nearly decade old bitcoin is facing. The main difference though is that the ethereum blockchain is much more complicated than bitcoin blockhain. The ethereum blockhain is intended for Distributed Apps(Dapps) which will run on the ethereum network and paid for in ether. We still haven't seen an real use of it other than all the ICOs recently promising some new product or service. For me, the real strength of Ethereum is core team which fixes all the issues very promptly and make sure the blockchain is upto data.