Cracked Apple Logo on Macbook Pro

As long as you keep foreign substances out, there is not likely to be any long-term impact of a cracked Apple emblem.

The Apple store will be happy to fix it by replacing your entire display at a cost north of US$400.

You could buy a Mac with a dead display screen (or just a screen as a non-working part) on ebay for short money and swap it yourself.

One big problem for self-repairers today is that Apple has reduced the number and increased the complexity of their field-replaceable units, and the individual parts you want may not be available as new. Today, they tend to swap the display-assembly-with-aluminum-cover as one unit, and do no small individual parts (like screen cover-glass or Apple Emblem) replacement.

That does not stop the used market from producing the used parts you need, but it makes everything more complicated.

without seeing the crack it is hard to tell if it will affect your computer screen in any way in the future.

May I suggest you consider placing a wide piece of clear packing tape over the logo in hopes of keeping it stable and make an appointment to see a Genius at an Apple store ASAP. They can give you the best advise possible and also pricing to decide if you need to move forward.