I tend to search for answers to coding problems. It seems that MrTaggy either provides better results or no results than a traditional search engine.

I think 20+ words of context around the tag words from the page would be more effective.

Have where it is possible to filter the results based on the user language..

Currently the presentation of the results is competing with the bright eye catching tags next to each result. If the UI would be better balanced then the usability would support the user interaction with more people spending more time on the site.

Especially for less mainstream search interests, there is often nothing tagged yet. So the user is left without a results list (though the 2 "quicklinks" are already a step towards mitigating that).
I suggest to establish a way, to include "search terms", that are then matched to 'text-on-page' instead of matched to tags. In the search box, the syntax could maybe be to enclose such a term in "..." .
This could help to prevent users having to "leave" for google when hitting a rare search term.

I'd like the option of turning off the thumbnails. These do not provide much help when searching for highly technical items.

Tags to pages that aggregate results tend to return results that are less useful than ones to actual pages.

I think other search engines, and pages like trip-advisor or shopping.com should be blocked from results in favor of the 'primary' sources.

porn filter

Replace the thumbs up / down with plus / minus, thought I was voting for the term, not adding a filter to the search.

I want to be able to see only the results containing ALL tags regardless of how many or how few sites there may be with this characteristic. It least it would be more organized.

Mr Taggy queries should match the titles of bookmarks, not just the tags