The impact of the changes will vary, drastically, based on your specific tax situation. I would definitely consult a CPA for specific situations, but will provide some general observations (highlights/lowlights).
If you are a W-2 employee, you have lost the ability to deduct unreimbursed business expenses (falls under the previous miscellaneous itemized deductions category which has been eliminated). You've also lost the ability to deduct moving expenses. You will also be taxed on employer-reimbursed moving expenses. To offset the effects of these items, the standard deduction has been doubled to $12,000 for individuals and $24,000 for married couples filing jointly. (See top of pg 4)
If you are a 1099 employee, you may now only be subject to income tax on 80% of your income instead of the full 100%. (See pg 5).
Note that many provisions of the bill are still vaguely worded enough so as to cause tax professionals I work with to question how they will be applied this year and they are awaiting further clarification from the IRS.