It used to be that when Google made major changes to its search algorithm there would be a few days of shifting results and the new regime would settle into place. As Barry Schwartz notes, the back and forth used to be called the Google Dance." These days the process is quite a bit more complex and, with the current Panda algorithm, is taking place over the course of months a bit at a time.
I'm going to give you two examples, one related to link-building and the Panda algorithm, the other related to mobile searches, which I think is separate from Panda. In the process, I'll point out how both mistakes can be avoided by simply doing what's best for your visitor rather than trying to game Google.
Panda No Like Link Schemes
A major aspect of Panda addresses what Google describes as link schemes." These can include widely used tactics, which are widespread because they used to raise sites in search results, such as:
Widely distributed links in the footers of various sites"
Forum comments with optimized links in the post or signature"
Links with optimized anchor text in articles or press releases distributed on other sites"
Here's a paraphrase of Google's example for the third item above:
There are many djs on the market. If you want to have a party, you will have to pick the best dj. You will also need to buy flowers and a disco ball."
Each of the above links might go to a site's homepage or separate pages on one site which are being optimized for those specific terms. The idea is to get the site or page to the top of Google's search results for the particular linked terms.
What that means is that people who've used such tactics on the web may now have a lot of cleaning up to do. If they used them on your behalf so that you rank highly on a particular term, then you may experience a sudden drop from page one results to might as well not even be listed results.
But consider the usefulness of those links to the reader. If the article or press release is about your site, which is presumably clearly identified, then having a bunch more links to the same site doesn't really help the reader. In fact, if all the links go to your homepage, then a reader who's actually interested may click each one only to discover that they all go to the same place.
If you were focused on the reader from the beginning, then you wouldn't have to go back and clean up those mistakes, some of which may be out of your hands at this point.
For more on Panda and linking schemes, see these posts from Search Engine Land:
Google Warns Against Large-Scale Guest Posting, Advertorials & Optimized Anchor Text" In Press Releases
Google's Matt Cutts: Linking 20 Domains Together Likely A Cross Linking Scheme"
Now You Have to Worry About Mobile Searches Too
As mobile web use continues to grow, mobile search grows along with it. Google has made in clear that they will be downgrading sites in smartphone search results that serve the reader poorly. In fact, they clearly discuss common configuration mistakes" in relationship to the site visitor:
Avoiding these mistakes helps your smartphone users engage with your site fully and helps searchers find what they're looking for faster. To improve the search experience for smartphone users and address their pain points, we plan to roll out several ranking changes in the near future that address sites that are misconfigured for smartphone users."
While responsive design for your site is one solution, the old school method of redirecting site visitors to mobile optimized pages is still acceptable unless you do the following:
Some websites use separate URLs to serve desktop and smartphone users. A faulty redirect is when a desktop page redirects smartphone users to an irrelevant page on the smartphone-optimized website. A typical example is when all pages on the desktop site redirect smartphone users to the homepage of the smartphone-optimized site."
Note the use of the term irrelevant." That speaks to the needs of the visitors, not the needs of the site owner or web designer. Fulfilling the visitor's needs is the best way to address such changes now and for future algorithmic updates.
Optimize For Site Visitors and Create Great Content
If you dig into the above posts you'll notice that Google is not only emphasizing optimizing your site for your visitors rather than for search engines. They also advocate creating good content" in order to attract organic links from other sites.
I'd urge you to skip good" and start creating great content, content that is as wonderful as your music.
And if you're interested in keeping up with specific changes and digging into more details, Google's resources for Webmasters is the place to start.
More: 9 Top SEO Tips For Musicians