I have to disagree a bit. In my opinion ethernet isn't necessarily useless w/o SSL.
If you want to do something that requires login or to send data over public networks (aka Internet) you should encrypt it. And the webservice that i wanted to use only allows https-secured connections...
Also, it's not common to list limitations. Instead features are listed. You won't be able to stream 1080p videos with a Netduino Plus too, for example. In my opinion that's obvious. The processor speed and RAM just won't allow it.
I think that's a bit different as .Net Micro supports SslStream.AuthenticateAsClient but the Netduino throws a NotSupportedException. :net Micro doesn't promise to show video at all.