Two way integration with Salesforce!
Right now we cannot enter a lead into Salesforce and have their information migrated over to Hubspot, unless we export to a csv file and import that to Hubspot, which is TOTALLY missing the point of "integration."
This now exists and is available to everyone! You can set up the bi-directional sync between HubSpot and Salesforce using this guide: http://help.hubspot.com/articles/Tutorial/enable-the-bi-directional-sync-between-hubspot-and-salesforce.
Richard Cedrone commented
True two way integration would allow you to delete a contact in SalesForce and it would automatically archive the contact in Hubspot. Today it is a two-step process and needs to be addressed ASAP please.