I realize I'm probably an outlier in that I since I semi-ER'ed in April 2013 I've spent a full 5-7 months a year traveling, usually about 90% international, 10% domestic.
Domestic portion is usually dirt cheap (i.e., camping, staying with friends, etc.).
My international travel includes a few very different styles. The traveling I do on my own is pretty expensive because of far-flung destinations (e.g., Africa, Central Asia, Asia, etc.), even when traveling 2 star.
I also accompany my elderly mother on many lengthy international cruises per year, which as someone else mentioned, can actually be very cost effective (and is the only way she wants to travel now at age 86). But they can also be interesting as we tend to go to fairly exotic/distance places as well (e.g., segments of world cruises).
For all of 2014 (still one trip leaving in November), my travel costs will amount to about $30,000. Note that this includes about $1600 in visa costs, $4600 in airfare (not even counting one free international and one free domestic FF award ticket!), and $3100 in travel insurance costs. (i.e., almost 1/3 of the total is not tied to how luxuriously one travels). For my independent travel (i.e., going it alone), there is additional cost b/c of traveling as a single (which all singles should be aware of in calculating budgets). For the family cruises, I can share the cost of a double room, so that lowers the daily cost. This $30K is out of a total $80K spending including taxes.
For 2015, I plan to spend about the same amount -- maybe a little less because one of my international trips will be a few months in South America where I used to live so can stay with people much of the time and lower my lodging costs. Still, I'm sure I'll spend a lot.
I haven't been anxious about this level of expenditure I think because I've been doing a little consulting work since I left full-time employment, and the extra income psychologically helps me to feel okay about such 'splurging' -- but honestly FIRECalc and all the other analysis says I'd be okay even without that income, so I'd probably do it regardless..
Anyway, obviously travel is a big ER priority for me, much more than most people, so I wouldn't expect that others would necessarily budget this much. I do expect to keep this level of travel spending for several more years at least. I especially want to visit all the physically more challenging places sooner rather than later, since I won't want to be lugging that backpack around forever I'm sure......(I'm 59 yo now.).