In reply to Matt.

Hi Matt,
Jetpack might be for the develper if this plugin system provides an API. :)
I like many of the tools from Jetpack (Jetpack comments, subscribe to posts), but how they function is very general. For examplet the CSS/JS libs are included on every page, even if the tools aren't use on these pages. I guess this is something what a user means if they say that Jetpack will slow doen your website. Most Jetpack tools doesn't provide options for the experienced user and require to use other Jetpack tools too: To add the Jetpack subscription option to your contact form you need to use the Jetpack contact form wich is very limited in functionality. I really would like to use Jetpack on every website, but need to consider this choice most of the time.