legitimate - looks like it is. new - no! online software has been available for decades.
If you are used to using the Desktop CD program you may not like doing it Online. There are some big differences as explained above. When you are done be sure to download and save both the PDF and the .tax2018 data file to your computer so you can access them in the future if you need a copy or ever need to amend.
If you do decide to switch to Online here's how to Transfer 2017 from your computer.
https://ttlc.intuit.com/questions/1900883-how-do-i-transfer-last-year-s-return-to-turbotax-online
What's the difference between TurboTax Online and the TurboTax CD/Download?
TurboTax Online and the TurboTax CD/Download products are very similar and both cover most tax situations. The majority of our customers choose TurboTax Online to confidently file their taxes.
Here are the big differences between the two:
1. If you file online, we store all of your information on our secure servers. If you use the CD/Download, you need to save and store your own tax return.
2. With TurboTax Online, you can work on your taxes from any computer or mobile device with Internet access. With the CD/Download, you install TurboTax on your computer and you can do your taxes without the Internet.
3. The CD/Download product is a better overall value for people who prepare tax returns for their friends and family. It allows you to prepare and print unlimited federal returns and e-file up to five at no extra cost.
There are some tax situations that TurboTax Online does not cover. If you need to file corporate, partnership, and estate/trust returns, or 2015-2017 amended returns, you'll need to use the TurboTax CD/Download products.
And continuing:
4) There is no "Forms Mode" in the Online software
5) (further to #3 above) Online software only allows you to file ONE Federal tax return, with it's associated states. If you have more family members to help file for, you have to create an entirely new account, and pay all the software charges again unless the person can use the "Free" version...but that still requires a new separate account. (We can't overstress how important it is for you to keep a written record at home of your EXACT UserID and Pwd for every Online account you create)
6) IF you use an Online account for future successive years, you can access any prior years taxes that were filed from that exact-same Online account if: a) you make sure you use the exact same UserID every year and b) you pay for the Online software in the next year. Access to prior years is available for any account (PLUS or higher) for ~ a year to 1.5 yrs...but after that, you have to pay for the next year's online software in that account...or the prior year data may get locked up until you pay (of course, if you download and save your PDF file for that tax season every year..then you already have your own copy...as long as you back it up off computer for your eventual computer HD crash.
7) If you use ItsDeductible with an Online account to import charity data, the UserID for your ItsDeductible must be exactly the same as your Online TurboTax account's UserID