At risk of repeating some of the advice that Lego has given...
I think placeholders are fine, but you have to be careful when using them because more than you think can be encompassed by names depending on the setting - for instance profession, lineage, expectations of the parents, culture, location. So in this regard, I actually think that it is better to use a "wrong" name instead of a "blank" placeholder - you just have to make sure to catch all of the corrections needed in the final draft so that a random "Steve" doesn't just appear out of nowhere! - and make sure that you have groups of names for characters and things that all share similar backgrounds. The main thing is to make sure that you do not lose the personality and individuality of the character/setting by obscuring the name with a place-holder - the name can be a placeholder, but the actual thing you are writing cannot be.
But, even Brandon Sanderson changes the names of characters and places over the course of his drafts - He revealed a name change of a main character during his writing process in a recent Q&A I think (although I think the character was originally named some 20 years prior to the writing of the book series...).
Of all of these things, the least important to have a finalized name for is the name of the story - this can absolutely change and in a lot of ways is better served by being reactive to the final story product, rather than informing the story itself.
Hope that all made sense, rushing before I have to leave for work...!