Who cares if Amazon's (AMZN - Get Report) stock is trading at 152 times forward earnings estimates, it's a mind-blowing tech company crushing the life out of retail corpses like Sears (SHLD) . Hence, maybe it will grow earnings 300% sustainably at some point. If not, no big deal since Amazon is Amazon.

Netflix (NFLX - Get Report) at 91 times forward earnings estimates? No worries there either -- Netflix has hooked the world on watching movies on-demand and may deliver 100% earnings growth every single quarter in 2018 and beyond. If not, Netflix is still Netflix.

Investor optimism on big tech names like these, along with social media king Facebook (FB - Get Report) and chip giant Nvidia (NVDA - Get Report) , have continued into the first week of January (see shaded area in below chart). To investors, these companies can do no wrong and deserve even higher valuations. Pure invincibility syndrome.

Ultimately, it's a short-term bullish indicator on the market that these arguably over-stretched momentum stocks, which were a key driver of the sentiment in 2017, continue to be in favor with investors.

At some point soon though investors will have to assess whether they are too optimistic on these hot tech trades. For the time being, might as well ride the horse until it drops dead.

Facebook and Nvidia are holdings in Jim Cramer's Action Alerts PLUS Charitable Trust Portfolio. Want to be alerted before Jim Cramer buys or sells these stocks? Learn more now.

Tech stocks continue to be on fire. Source: Bloomberg
Tech stocks continue to be on fire. Source: Bloomberg

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