Hi
I have to agree with both, having links to external websites isn't a bad thing, IMO it adds value to your website.
A simple way of looking at Google is that it was create by some university graduates who we're taught, like everyone at uni is to reference where you get your information from. So when they started 'Google' (I know it wasn't called Google initially), they used the fact if you linked of to somewhere it was like saying this website is a good source of information and the more links pointing at a page the more authoritative it must be, then came along SEO's who realised this and abused it and now you have a situation whereby too many spammy links will actually hurt your rankings.
But the core part of the algorithm which still helps rankings is outbound links, so if ever webmaster remove outbound links, google would suddenly struggle to rank websites.
Just image you are writing a university essay, does the link (source) add value to your article.
In terms of links in your footers, this is a bit different, this was an old black hat SEO tactic to stuff keyword anchor text links into your footer to boost other websites you owned, so links in the footer, think of more a user experience point of view rather than SEO, but a great question was asked on here (http://moz.com/community/q/sitewide-footer-links-bad-or-not).
Hope this was useful.
Thanks
Andy