For both of these services, the email address and password for the account are sent to Motorola. Both services support a mechanism (oAuth) explicitly intended to make this unnecessary, but Motorola does not use that more-secure mechanism. The password is only sent over HTTPS, so at least it can't be easily intercepted by most third parties.
Most subsequent connectivity to both services (other than downloading images) is proxied through Motorola's system on the internet using unencrypted HTTP, so Motorola and anyone running a network capture can easily see who your friends/contacts are (including your friends' email addresses), what posts you're reading and writing, and so on. They'll also get a list of which images you're viewing, even though the actual image download comes directly from the source... More at Beneath the Waves.
This will either worry you or fly past you.