[TriMe]

For 3.7.* users who would like something like the attached image

In memberinfo_block_contatinfo look for

	<if condition="$prepared['hasimdetails']">
		<fieldset>
			<legend>$vbphrase[instant_messaging]</legend>
			<div class="fieldset_padding floatcontainer">
				<div><phrase 1="$prepared[username]">$vbphrase[send_instant_message_to_x_using]</phrase></div>
				<ul class="list_no_decoration" id="instant_messaging_list">
					$block_data[imbits]
				</ul>
			</div>
		</fieldset>
	</if>

and replace with

	<if condition="$show['hasimicons'] OR $userinfo['field6']">
		<fieldset>
			<legend>$vbphrase[instant_messaging]</legend>
			<div class="fieldset_padding floatcontainer">
				<div><phrase 1="$prepared[username]"></phrase></div>
				<ul class="list_no_decoration" id="instant_messaging_list">
					$block_data[imbits]
                          <if condition="$userinfo['fieldXX']"><br />
			<td><a href="http://www.facebook.com/profile.php?id=$userinfo[fieldXX]"target="_blank"><img src="../images/misc/im_facebook.gif"border="0"alt="View Member's FaceBook Profile"></td></a>&nbsp;
			<td><font color="#938d91" size="1">Facebook &nbsp;<a href="http://www.facebook.com/profile.php?id=$userinfo[fieldXX]"target="_blank"></font>&nbsp;<phrase 1="$prepared[username]">$vbphrase[visit_x_facebook_profile]</phrase></a></td>
			  </if>
				</ul>

			</div>
		</fieldset>
	</if>

Replace [fieldXX] with the field number of your Facebook profile field

Replace ../images/misc/im_facebook.gif with the location of your facebook gif, and rename it accordingly.

Add New Phrase in Phrase Manager with varname: 'visit_x_facebook_profile' and text: 'Visit {1}'s Facebook Profile'

Search in admincp Phrases for $vbphrase[instant_messaging], replace with what ever you want. I chose Messaging and Social Networking.

Cheers