Hi there!
This review is missing at least one important - for me the most important - point: the scripts of the services are only loaded if the user hovers over the icons/services not earlier! So it doesn't slows the site down, as a lot of other plugins do, as of my knowledge Jetpack included!

To compare it with Jetpack is really bad IMHO: Jetpack is an overbloated plugin suite but "Floating Social Bar" follows an open source software principle: do only one task but do that really well! --- This plugin succeeds with that: simple, well-coded, lightweight, easy to use. Period.

Just my 2 cents :)