For the MongoDB connection, you just have to run the meteor application with the help of the meteor run command but only in one session, refer to the following command:
[kfullert@shotgun ]$ meteor mongo
MongoDB shell version: 2.2.1
connecting to: 127.0.0.1:3002/meteor
After that, you have to use the URL that is there in the "connecting to" command including the standard mongo tools:
[kfullert@shotgun ]$ mongo 127.0.0.1:3002/meteor
MongoDB shell version: 2.2.3
connecting to: 127.0.0.1:3002/meteor
>
For mongoimport, you have to do as follows:
[kfullert@shotgun ]$ mongoimport -h 127.0.0.1 --port 3002 -d meteor