And then there is FATCA - prepare for your bank/brokers to have a bad reaction when you break the news to them.
If you have to sell stock, you may want to do it before setting foot in US - to
avoid having to report it on your tax return.
Ask your company if they can help you file your first tax return, because you will struggle with that. First and last year are "dual status" years which TurboTax can not handle - only foreigners have dual status years.