Everybody gets so excited about figuring out how to wrangle Google. The answer has been, is, and will ever be to create relevant unique content. From the standpoint of the typical blogger, the Panda release will only be good news. It will punish some of your would-be competitors without hurting you one bit if you make sure of the following:
The short answer @joseph is that your clients will know already if they've been affected or not. The Panda/Farmer update hit several months ago now and sites that were hit by the update saw their rankings and traffic decline immediately. If your client sites are still drawing in the same levels of organic search traffic as pre-Panda, it's fairly safe to say that their content sourcing strategy is ok with respect to Panda/Farmer. It's the next update you want to be worried about (no I don't know what the next update is going to do). The best strategy is to remain white-hat, follow the industry blogs and continuously adapt.
Panda might have introduced bounce rate as a ranking signal . What does that mean? We've known for a long time that bounce rate is a half-decent proxy for how useful the page is from a visitors point of view. It follows that the search engines should use this metric to understand better the usefulness of content, and thus contribute to how a page should rank for a particular query. There continues to be chatter amongst the SEO world on this topic - it seems like a no-brainer to me. Again - unique, useful content wins.
From some brief research it appears you will have to fit the google guidelines of good content.
Outsourcing specifically isn't an issue, outsoucing to copy / paste merchants will see your site die.
Have a look at SEOMOZ blog, there are some recent posts about this update:
Does the site have duplicate, overlapping, or redundant articles on the same or similar topics with slightly different keyword variations?
Does this article have spelling, stylistic, or factual errors?
Are the topics driven by genuine interests of readers of the site, or does the site generate content by attempting to guess what might rank well in search engines?
Does the article provide original content or information, original reporting, original research, or original analysis?
Is the site a recognized authority on its topic?
Is the content mass-produced by or outsourced to a large number of creators, or spread across a large network of sites, so that individual pages or sites don’t get as much attention or care?
Is this the sort of page you’d want to bookmark, share with a friend, or recommend?
Does this article have an excessive amount of ads that distract from or interfere with the main content?
Would users complain when they see pages from this site?
Would you be comfortable giving your credit card information to this site?
Your blog will benefit from two reasons:
1) Sites in front of you in search rankings got knocked down to be below you instead of above you.
2) As long as you have enough content in your blog entries, you will be seen as higher quality content, which from now on gets you more of a boost.