I've heard nothing but good things about RelateIQ. I played around with it very briefly and found it was overkill for my needs. I'd love a simple spreadsheet of information about people (such as title/company, twitter handle, linkedin URL) that subscribe to my various email lists (blog, Startup Edition, and Product Hunt).
What do you use it for, @shedd?
Agree Ryan, seemed very enterprise focused (not a bad thing)...ie $40+/mo per user. I dabbled with www.cloze.com but didn't find it to be that easy of an experience. Very interesting that with Yesware, Newsle, Boomerang, etc like tools you can be on the "offensive" of engaging with your network but there aren't many tools (at least that I'm aware of) to re-surface disengaged folks and spur re-connection.
A combo of Boomerang's "ping me in X days if no response" feature and Rapportive should do the trick.
Or followup.cc + Rapportive
Or https://www.contactually.com/ (Cheaper than RelateIQ but still priced high for personal use).
I use RelateIQ for fundraising and our biz dev person uses it for relationship management. It really is a great tool. Probably a bit "pricey" for what we really need it for ($50/month/user) but ultimately small price to pay for the ease of mind that everything is in one place that we trust.
I'd strongly recommend it.
RelateIQ just announced their iPhone app: http://www.producthunt.co/posts/relateiq-for-iphone