I always have this fear in mind while choosing domain names. So, what if tomorrow a company decides to grab our domain? Can they do that :(
Well, it's 2010, if a company hasn't got its act together by now and bought the domain names it requires it probably never will do!
Saying that you have to be careful of "passing yourself off" to being that specific company when buying the non TLD names.
For example with my company name I own example.com/info/biz/asia/com.br/cn/de/in/mobi/tel/us yet someone else managed to grab .eu and has never done a thing with it HOWEVER if they were to and try and pass themselves off as my business they would know about it very quickly.
If they were to trade as example.eu in a totally different line of business, like most names are now, then no harm done however don't try and kid yourself by buying a registered trademark, even a non-global one, and imagine you may get away with it unless you can demonstrate a prior and valid usage.
For popular names I suggest to customers to consider their business or trading name plus the town so for a popularly named hotel say exampletown.co.uk. I have one customer like this and there are, believe this or not, a minimum 150 hotels with their unique exampletown.co.uk, it works well.