When I started my practice back in 1993, I paid for a real listing in Martindale-Hubbell (as opposed to the cheapie listing in the front blue plages) that I kept for four years. By 1997, I’d not gotten so much as a phone call from the listing.  Looking forward, I realized that my website (that I developed myself and went live in late 1995) was already generating more visibility for me than the M-H listing – and so I declined to renew it.

Seems that I was right, as this posting from Wired GC bears out:

When I was at the offices of one of my outside counsel this week, I
noticed part of the 2005 edition of Martindale-Hubbell sitting in two
huge boxes in a conference room. Not this many
but still a hefty set. They do look good on the shelf (often a required
back-drop for lawyer interviews), but their days have to be numbered.
M-H does offer CD and online versions, as well as search through lawyers.com.  All good information; but I haven’t used M-H in years.

closed system used by Martindale-Hubbell doesn’t really work anymore.
A9 is a threat, but the bigger challenge is a general counsel who calls
a colleague for a referral, checks the firm website, and Googles them.
Perhaps you check Martindale, but it’s no longer the gold standard.

(from The Wired GC)