Sending your friends/family/colleagues a link on MegaUpload (or similar) was essentially putting a paywall between them and the file you actually wanted to give them. For pirated content it makes sense, you have no concern for who comes along to download it and of course they gave you a cut of the money too: http://www.groovypost.com/howto/review/paid-to-upload-upload...
For <legitimate work> it's just nonsense when there's so many high profile, easier ways to get that file from a to b.