I use two of them and they haven't given me any trouble. Pinboard[1] adds a menu option, which I have positioned next to the address bar. Pinboard Right[2] adds a 'Post Page to Pinboard' link to my right-click menu.
The official extension is quite basic. Here's a screenshot that shows literally every feature: http://i.imgur.com/sMVY5.png
"Save to Pinboard" and "Read later" work exactly like the bookmarklets, and the four items below the divider are just convenient links to different parts of the Pinboard website. "Save tab set" is fairly useful for moving sessions across machines.
1. Pinboard: https://chrome.google.com/webstore/detail/lclbbneapfiaihigbk...
2. Pinboard Right: https://chrome.google.com/webstore/detail/mpiepoibcfbjicpaic...