I need a CRM which takes subscribers' names from our site and handles them cleverly

We are a small web publisher with 9 staff, of which two are admin/social, based in the Philippines.

We find it hard to handle our relationships with advertising subscribers, with whom we now interact purely passively. We would like proactively to track what they are up to, to republish and linking to their content, as well as periodically reminding them that we are here to help.

We also find it hard to add new prospects to our CRM / mailshot / interaction activity, since we don't have time to laboriously enter all of a prospects' details by hand.

We presently use Zoho CRM Free for 3 users and hold around 50,000 names, many very old. Our use of Zoho CRM has maybe been handicapped by it being free, so we have not attached their mailing facility, and by the fact that we haven't joined it to Google Apps. We have been reluctant to test these activities for fear of discovering that the outcome didn't match our expectations - Zoho is a somewhat clunky product which our staff have not adopted enthusiastically - and for fear also of losing our free status, given the large number of our contacts the Zoho CRM services. In some ways we like Zoho - it is configurable. In other ways, not so much - it is not very "automagical" and not very oriented to social.

We would like a system which:
[1] Takes new subscribers from our site and puts them into the CRM
[2] Integrates with gmail (maybe gmail apps) and allows cross-company visibility of contacts and mail activity across several gmail acounts.
[3] Allows us to schedule group mail-sends, and reminds us when to do so, according to our subscribers' sign-up date.
[4] Relates emails sent to and received from subscribers to their CRM record, so when we open the record, we see past correspondence
[5] Tracks subscribers' Gmail, Linked In, Twitter and Facebook activity (connections to this being supplied through our initial onsite contact form) and delivers this activity to us via the CRM, viewable via easy saved searches or a daily "to do" list.
[6] Has a leads facility which gathers data from external web sites that we notice as being potential partners more or less "automagically", i.e., without a lot of keystrokes, so that we can target initiating and growing our relationship with them.