Personally, I'm starting to be fed up with them. They can be used to disguise links to spam and self-promotion. Security experts are recommending against them, such as in this blog at ZDnet:
http://blogs.zdnet.com/feeds/?p=664
The safe thing to do with normal links is to hover over them to see the actual domain that you will be sent to. With URL shortening, that doesn't work. I have figured out how to preview tinyurl links using preview.tinyurl and yes I now have a cookie to always preview at tinyurl. But, there are many more sites for shortening that I've never heard of and have no idea if they are trustworthy. I just saw a new one today in this post. I checked out the site the long way around -- the safe way -- and found that the way that they do previews is different than tinyurl. I really don't want to have a cookie for every one of these sites. I still have no idea if isgd can be trusted anyway.
Finally, these sites can be hijacked to send every link to spam or malware as recently happened with cligs:
http://blog.trendmicro.com/who.....d-for-now/
