Ok, this is not my work. But it deserves to be shared. Here is an OSNews comment about GPL vs BSD :
If you want to give your software away for free, use BSD. If you want to share your software, use the GPL.
Software under the GPL is not free. Microsoft office is not free, you have to pay Microsoft money. The Borland developer tools are not free, you have to pay Borland (or whatever they're called these days).
Lastly, software released under the GPL is not free: if you choose to copy and paste GPL code into your own program you have to share it. This is how you pay for GPL code. This is a very egalitarian idea: I share my code, and if you use it in your own program, you pay me back by sharing your code or else you ask me to relicense the code under a different license to suit your needs (which was always possible).
To make sure no-one can escape sharing (after all, this is how they're paying to use the software), GPL v3 requires the following
(a) You make the source code available
(b) You don't use patents to prevent people from using your code, which would effectively block code-sharing despite (a)
(c) You don't use DRM to prevent people from using your code, which would effectively block code-sharing, like (a)
The GPL is no more viral than any commercial license, the only difference is in how you pay to use the software. And it's always worth remembering that you don't have to share until you distribute the source-code (and as corporations are legal entities, you can give a copy to all your 1000-odd co-workers without legally distributing it). It's further worth remembering that if this is a problem, you can always ask the original author to re-license their work under a commercial license if you would rather not share.
This GPL is viral/evil/not-as-cool-as-BSD thing is rubbish. It does what it sets out to do: encourage people to share code. There's no excuse for "accidentally" using GPL code in your own software, just as there's no excuse for "accidentally" installing a pirated copy of MS Office on your friends PC. Both place value on software, and if you choose to use it in a certain way, then you have to pay for them: the only difference is in how you pay.
From Bryan Freeney.
Just an additional opinion: A lot of people bash GNU GPL because they feel it's too much restrictive. Disliking the actual concept of copyright, I feel sympathetic about them. However, what they often fail to grasp is that GPL is a licence made to mimick, in the copyright world, what would be a copyleft world. It is surely paradoxical the fact that the GPLv3 restrictions mean more freedom, but it's true, if you count the other's freedom as much as your one.