Time might come, and might be around the corner when, images in Google Search will be OCR'd (scanned for text/wording and made searchable) this will result in your watermarks if its in Copyright Joe Smith (text form) will be searchable.

Also thing about this if you are using image search with an image of your brand, (not sure about practically but theoretically) you should be able to find all your images if they are watermarked with your Brand image in Google image search.

So if you are planning to future proof your images for image SEO go for it!

So if you read around on the topic Google supporting AJAX is a recent development so there are still many issues, with this. Think of it this way if Google bots still have a hard time reading regular code after so many years now. AJAX will have issues, they are focusing from what it seems on commenting systems such as FB, and Disqus. However try it out and see if your AJAX is being read if not it might be some time before most of the AJAX crawling works as it should.

Hope this helps

More info: http://searchengineland.com/google-can-now-execute-ajax-javascript-for-indexing-99518

and http://moz.com/community/q/can-google-read-ajax

No it does not, and here is one glimpse as to why:

"Google does indeed sometimes launch algorithms just for the English language but when possible, Google does try to launch them globally."

More info: http://searchengineland.com/googles-matt-cutts-we-fight-search-spam-in-40-localized-countries-internationalize-our-spam-algorithms-168785

Hope this helps

Yea I would limit this to a lower number to few important comparisons not all highest, lowest, and few middle priced, and maybe most know stores. Adding content will help to mitigate this as well. But if its under 5 I dont think that should be a red flag

Removing was probably a safe bet. Why are you considering putting it back?

Does it help your customers? No, then dont put it back. Yes, then maybe, why does it look over-optimized to you?

Can you explain a bit more of what you mean by, "The product name in the product column is the name from the actual website I am tracking. As such, my keyword was appearing sometimes up the 30 times." ? Is it in a product descriptions with significant amount of information that is relevant to the customer? If so, then you can edit the text to make sure your keyword density is below 10% or 5% just to be on the safe side. Unless you mean something else by the product column. Like Peter said adding relevant content to balance the keyword ratio could really help, fundamentally relevant content is great its great for SEO, if that is possible.

The best post/information I came across was what Geoff has written here: http://moz.com/blog/site-speed-are-you-fast-does-it-matter

Under How important is Site Speed? In two words summary of Google and Matt Cutts reply is that its a factor, but a very small factor of the many factors involved in rankings.

I am also interested in this question as much as you are, but in my efforts I haven't seen a noticeable change in rankings just solely related to speed, this includes TTFB and other speed improvements.

Having said that. TTFB and overall speed optimization is important in conversions on your site and ultimately in providing better user experience, which is always really important.

This leads to another question that you can ask, did improving TTFB improve conversions, or lower bounce rate, etc? This also is a great question, that I am curious in as well.  From my end I did not have a client that was that worried, or had a horrable TTFB that I could measure and notice a difference, but very interested if someone had this effect

Hope this helps