I always thought vodka was just alcohol and water, and that the ideal vodka was one lacking all flavor components characteristic of the grain or potato mash that it was distilled from. I once saw a vodka process diagram showing multiple distillation and charcoal filtration steps--suggesting an effort to remove all flavor components. But looking at the prices being charged for high end vodkas, I am wondering what the draw is. Are there flavor components in these high end vodkas that make them that much more desirable than pure alcohol that people pay more than $50 a bottle for them?
High end vodka is primarily good vodka+branding. You pay extra to get that designed bottle. Perhaps the manufacturer also does something extra that they claim makes the vodka special. Whether it actually does depends on what they have done.
Good vodka has most flavours removed. Some flavours - specifically those that both have a boiling point close to that of alcohol and the ability to pass through an active carbon filter will remain.