Everyone is trying to make sense of the changes to the Federal Tax Laws.  There are a lot of changes overall, but here are the specific changes that impact the residential real estate market:
1.  Mortgage Interest Deduction (MID) - Homeowner's can deduct interest on mortgage debt up to $750,000 (you used to be able to deduct interest on mortgage debt up to $1 million).
2.  The State and Local Tax  (SALT) Deduction is now capped at $10,000.  This includes property taxes.  Previously you could deduct an unlimited amount.
3.  Interest on home equity lines of credit is no longer deductible.  It used to be deductible up to $100,000 of mortgage debt.
4.  The Standard Deduction was increased dramatically.
There was discussion of changes to other real estate items, but ultimately, the following items DID NOT change:
1.  Homeowners who sell their home for a gain will still be able to exclude $500,000 from capital gains (if filing jointly, $250k for single filers), so long as they are selling their primary home and have lived in it for 2 of the past 5 years.  (There was talk of this changing to 5 out of 9 years, but ultimately no change was made).
2.  1031 Exchanges remain intact.  Investment property owners will continue to be able to defer capital gain taxes using IRC 1031.  (1031 exchanges of other non real property, which used to be allowed, have now been eliminated).
It can clearly be stated that there are not any new aspects of the tax code that aid the real estate market.  The best thing that happened is the capital gains exclusion and the 1031 Exchange laws stayed in place.  I am not an accountant, nor an economist, so I'm going to leave the heavy lifting to people who are.  There are quite a few projections out there with respect to the primary home market.  This recent article from Curbed, which includes statistical projections from Moody's Analytics in which they compare the projections using the old tax laws, and then the new tax laws, is probably the most interesting I have read.
Did you notice there's no mention of the second home market in articles like this?  Expert opinions and projections are difficult to come by on this topic.  Again, there are not any positives baked into the tax code for a personal use second residence.  The fact that a second home is a discretionary purchase has not changed.  So, the impact on the second home market will vary from region to region and person to person.  Those who are impacted positively by the other aspects of the tax changes will have more money for discretionary purchases.  Those impacted negatively, won't.  That said, with such positives in the new tax code for the treatment of business income, it could create positives for investors and developers.  
The tax breaks for businesses will become a significant counter point.  Will the changes, overall, make the wealthy more likely to invest in their business than invest in real estate?  Probably.  However, the wealthy are also very cognizant of keeping a balanced portfolio.  So, those who have always had a propensity to invest in real estate are likely to continue to do so.  Might they find a way to buy a "corporate retreat" rather than a "second home"?  There will certainly be ways that the new tax laws get manipulated.  
To be frank, the changes, overall, make real estate slightly less desirable than it was in comparison to other asset classes.  However, the changes are not dramatic enough to change someone's overall feelings about investing.  If you always liked investing in real estate, you will continue to, and, you will find ways to take advantage of the new tax laws.  If you never liked investing in real estate, this won't get you started.  For those who were on the fence, a few will likely fall toward investing in other asset classes.  Since many people, in each of these categories, are likely to have more money in their pocket, it's impossible to make an exact prediction of how the second home market will be impacted.