Here is an excerpt from a recent email exchange with a client.

My reply
Yes, it seems recently that using keywords in their exact order can actually work against you (in some cases).  It really is best to just think of how your end user is going to be best served – and keep track of rankings you are most interested in and make slight adjustments from there.  Plurals are typically more popular.

As for categories, that’s a tough one.  Your product pages are doing great, but not your category pages.  Changing them like you suggest is worth a try (more descriptive names), so is adding text to these pages, and perhaps a text link (hyperlink).  What I like to do is try a little of both, track the rankings, see what Google likes best for your website and adjust from there.  I do not believe its always the same case in all matters.  There are a lot of factors (triggers) at play to know exactly what is going to work for one site any more.  Not everyone gets this though; and that is to our advantage.

Tweak a little here and a little there.  Keep track of what you are doing and what works and does not work, learn and adjust.  Get a new website or two to link to you every month, and you will be well on your way to rankings that might just surprise you!