Erm, this became rather longish... so long story short: the Sound preferences capplet was mostly redesigned and the whole section of the documentation covering it should be rewritten. Most, but not all of the changes are the following:

#: C/goscustdesk.xml:2660(title) C/goscustdesk.xml:2666(title)
msgid "General Sound Preferences"

#: C/goscustdesk.xml:2661(para)
msgid ""
"Use the <guilabel>General</guilabel> tabbed section of the "
"<application>Sound</application> preference tool to specify when to launch "
"the GNOME sound server. You can also enable sound event functions."

-There is no more General tab, this functionality is now in the Sounds tab.

#: C/goscustdesk.xml:2661(para)
msgid ""
"Use the <guilabel>General</guilabel> tabbed section of the "
"<application>Sound</application> preference tool to specify when to launch "
"the GNOME sound server. You can also enable sound event functions."

-The tool's title is now "Sound Preferences"

#: C/goscustdesk.xml:2684(guilabel)
msgid "Enable sound server startup"

#: C/goscustdesk.xml:2696(guilabel)
msgid "Sounds for events"

#: C/goscustdesk.xml:2701(para)
msgid ""
"Select this option to play sounds when particular events occur in the GNOME "
"Desktop. You can select this option only if the <guilabel>Enable sound "
"server startup</guilabel> option is selected."

#: C/goscustdesk.xml:2715(para)
msgid ""
"You must select the <guilabel>Enable sound server startup</guilabel> option, "
"and the <guilabel>Sounds for events</guilabel> option before you can access "
"the <guilabel>Sound Events</guilabel> tabbed section."

-These options are now called "Enable software sound mixing (ESD)" and "Play system sounds" 

#: C/goscustdesk.xml:2712(para)
msgid ""
"Use the <guilabel>Sound Events</guilabel> tabbed section of the "
"<application>Sound</application> preference tool to associate particular "
"sounds with particular events."

-Sound events is now Sounds, Sound pref. tool is Sound preferences

#: C/goscustdesk.xml:2739(para)
msgid "<guilabel>Sounds</guilabel> table"

#: C/goscustdesk.xml:2742(para)
msgid ""
"Use the <guilabel>Sounds</guilabel> table to associate particular sounds "
"with particular events."

-Sounds is now System sounds

#: C/goscustdesk.xml:2744(para)
msgid ""
"The <guilabel>Event</guilabel> column displays a hierarchical list of events "
"that can occur. To expand a category of events, click on the right arrow "
"beside a category of events."

#: C/goscustdesk.xml:2747(para)
msgid ""
"The <guilabel>File to play</guilabel> column lists the sound file that plays "
"when the event occurs."

#: C/goscustdesk.xml:2767(para)
msgid ""
"To associate a sound with an event, select the event in the "
"<guilabel>Sounds</guilabel> table. Enter the name of the sound file that you "
"want to associate with the selected event in the drop-down combination box. "
"Alternatively, click <guibutton>Browse </guibutton> to display a "
"<guilabel>Select sound file</guilabel> dialog. Use the dialog to specify the "
"sound file that you want to associate with the selected event."

-This is deprecated, there are no such elements in the window

#: C/goscustdesk.xml:2655(guilabel)
msgid "System Bell"

#: C/goscustdesk.xml:2798(para)
msgid ""
"Use the <guilabel>System Bell</guilabel> tabbed section to set your "
"preferences for the system bell."

#: C/goscustdesk.xml:2800(para)
msgid ""
"Some applications play a bell sound to indicate a keyboard input error. Use "
"the preferences in the <guilabel>System Bell</guilabel> tabbed section to "
"configure the bell sound. <xref linkend=\"goscustdesk-TBL-1\"/> lists the "
"system bell preferences that you can modify."

#: C/goscustdesk.xml:2805(title)
msgid "System Bell Preferences"

#: C/goscustdesk.xml:2823(guilabel)
msgid "Sound an audible bell"

#: C/goscustdesk.xml:2828(para)
msgid "Select this option to enable the system bell."

-bell is now beep

#: C/goscustdesk.xml:2834(guilabel)
msgid "Visual feedback"

-this is visual system beep now

Also there is a new tab, Devices, which is not documented at all, and replaces mostly the functionality of the multimedia systems selector, which is documented in the next chapter in Yelp.