I prefer to use the "adm" group for now.

--- src/journal/journalctl.c.orig	2013-03-08 14:14:13.671806583 +0100
+++ src/journal/journalctl.c	2013-03-08 14:14:44.462969574 +0100
@@ -881,16 +881,16 @@ static int verify(sd_journal *j) {
 static int access_check(void) {
 
 #ifdef HAVE_ACL
-        if (access("/var/log/journal", F_OK) < 0 && geteuid() != 0 && in_group("systemd-journal") <= 0) {
-                log_error("Unprivileged users can't see messages unless persistent log storage is enabled. Users in the group 'systemd-journal' can always see messages.");
+        if (access("/var/log/journal", F_OK) < 0 && geteuid() != 0 && in_group("adm") <= 0) {
+                log_error("Unprivileged users can't see messages unless persistent log storage is enabled. Users in the group 'adm' can always see messages.");
                 return -EACCES;
         }
 
-        if (!arg_quiet && geteuid() != 0 && in_group("systemd-journal") <= 0)
-                log_warning("Showing user generated messages only. Users in the group 'systemd-journal' can see all messages. Pass -q to turn this notice off.");
+        if (!arg_quiet && geteuid() != 0 && in_group("adm") <= 0)
+                log_warning("Showing user generated messages only. Users in the group 'adm' can see all messages. Pass -q to turn this notice off.");
 #else
-        if (geteuid() != 0 && in_group("systemd-journal") <= 0) {
-                log_error("No access to messages. Only users in the group 'systemd-journal' can see messages.");
+        if (geteuid() != 0 && in_group("adm") <= 0) {
+                log_error("No access to messages. Only users in the group 'adm' can see messages.");
                 return -EACCES;
         }
 #endif
--- src/journal/journald-server.c.orig	2013-03-08 14:42:35.535110912 +0100
+++ src/journal/journald-server.c	2013-03-08 14:42:43.846230680 +0100
@@ -174,7 +174,7 @@ static uint64_t available_space(Server *
 }
 
 static void server_read_file_gid(Server *s) {
-        const char *g = "systemd-journal";
+        const char *g = "adm";
         int r;
 
         assert(s);