First, the obligatory disclaimer: I'm not a tax advisor! That said, when we filed taxes in years we were doing Airbnb here in Denver, it was counted just like rental income, added into line 17 with any other rental income we had from long-term tenants. It's taxed like any other income you have, so you don't pay higher taxes on it.
Now, of course, if you're really good at Airbnb, then the extra income might bump you into a new tax bracket and at that point, you're paying more taxes.
Hey @Arthur Voskanyan , this isn't really answering your question, but to piggy back on what @James Carlson you'll also likely have to plan on paying lodgers/sales taxes on your gross vacation rental income depending on whether or not Airbnb can collect and remit on your behalf in your area. This is a big cost that some people overlook.
Airbnb Income can either be taxed as passive income from rental activities or ordinary income that is also subject to self-employment tax.
Factors such as the type of services you provide the tenant and the length of stay are factors that will determine how it is taxed.
Shorter stay and more services provide suggestion that is should be taxed as ordinary income.