Are there new features in 1.3 , and will any be available in pygame in the near future? Couldn't figure out a good google query.
 
 
 
One thing that changes is event numbers.  Event numbers are 16 bits in SDL 1.3 (as opposed to 5 bits in SDL 1.2), and all the event numbers except NOEVENT are changed.
Compare the two versions of  SDL_event.h  to see the differences; these google searches should find them:
 
A few months ago I wrote a little "display the name of a pygame event" function, and I tried to make sure it wouldn't break too badly with SDL 1.3:
 
from pygame.locals import *
_evnames = {}                                 # from SDL-1.2.14\include\SDL_events.h
_evnames[NOEVENT]         = 'NOEVENT'          #  0  SDL_NOEVENT
_evnames[ACTIVEEVENT]     = 'ACTIVEEVENT'      #  1  SDL_ACTIVEEVENT
_evnames[KEYDOWN]         = 'KEYDOWN'          #  2  SDL_KEYDOWN
_evnames[KEYUP]           = 'KEYUP'            #  3  SDL_KEYUP
_evnames[MOUSEMOTION]     = 'MOUSEMOTION'      #  4  SDL_MOUSEMOTION
_evnames[MOUSEBUTTONDOWN] = 'MOUSEBUTTONDOWN'  #  5  SDL_MOUSEBUTTONDOWN
_evnames[MOUSEBUTTONUP]   = 'MOUSEBUTTONUP'    #  6  SDL_MOUSEBUTTONUP
_evnames[JOYAXISMOTION]   = 'JOYAXISMOTION'    #  7  SDL_JOYAXISMOTION
_evnames[JOYBALLMOTION]   = 'JOYBALLMOTION'    #  8  SDL_JOYBALLMOTION
_evnames[JOYHATMOTION]    = 'JOYHATMOTION'     #  9  SDL_JOYHATMOTION
_evnames[JOYBUTTONDOWN]   = 'JOYBUTTONDOWN'    # 10  SDL_JOYBUTTONDOWN
_evnames[JOYBUTTONUP]     = 'JOYBUTTONUP'      # 11  SDL_JOYBUTTONUP
_evnames[QUIT]            = 'QUIT'             # 12  SDL_QUIT
_evnames[SYSWMEVENT]      = 'SYSWMEVENT'       # 13  SDL_SYSWMEVENT
                                               # 14  SDL_EVENT_RESERVEDA
                                               # 15  SDL_EVENT_RESERVEDB
_evnames[VIDEORESIZE]     = 'VIDEORESIZE'      # 16  SDL_VIDEORESIZE
_evnames[VIDEOEXPOSE]     = 'VIDEOEXPOSE'      # 17  SDL_VIDEOEXPOSE
                                               # 18  SDL_EVENT_RESERVED2
                                               # 19  SDL_EVENT_RESERVED3
                                               # 20  SDL_EVENT_RESERVED4
                                               # 21  SDL_EVENT_RESERVED5
                                               # 22  SDL_EVENT_RESERVED6
                                               # 23  SDL_EVENT_RESERVED7
_evnames[USEREVENT]       = 'USEREVENT'        # 24  SDL_USEREVENT
_evnames[NUMEVENTS]       = 'NUMEVENTS'        # 32  SDL_NUMEVENTS
def event_name(evtype):
    '''return a displayable name for a pygame/SDL event type number'''
    try:
        result = _evnames[evtype]
    except:
        if evtype in range(USEREVENT,NUMEVENTS):
            result = 'USEREVENT+' + repr(evtype-USEREVENT)
        elif evtype >= NUMEVENTS:
            result = 'ILLEGAL_EVENT_' + repr(evtype)
        elif evtype == 14:
            result = 'EVENT_RESERVEDA'
        elif evtype == 15:
            result = 'EVENT_RESERVEDB'
        else:
            result = 'EVENT_RESERVED' + repr(evtype-16)
    return result
# It's all gonna change in SDL 1.3:
#
#   SDL_FIRSTEVENT        = 0      # Unused
#
#   SDL_QUIT              = 0x100  # User-requested quit
#
#   SDL_WINDOWEVENT       = 0x200  # Window state change
#   SDL_SYSWMEVENT        = 0x201  # System specific event
#
#   # Keyboard events
#   SDL_KEYDOWN           = 0x300  # Key pressed
#   SDL_KEYUP             = 0x301  # Key released
#   SDL_TEXTEDITING       = 0x302  # Keyboard text editing (composition)
#   SDL_TEXTINPUT         = 0x303  # Keyboard text input
#
#   # Mouse events
#   SDL_MOUSEMOTION       = 0x400  # Mouse moved
#   SDL_MOUSEBUTTONDOWN   = 0x401  # Mouse button pressed
#   SDL_MOUSEBUTTONUP     = 0x402  # Mouse button released
#   SDL_MOUSEWHEEL        = 0x403  # Mouse wheel motion
#
#   # Tablet or multiple mice input device events
#   SDL_INPUTMOTION       = 0x500  # Input moved
#   SDL_INPUTBUTTONDOWN   = 0x501  # Input button pressed
#   SDL_INPUTBUTTONUP     = 0x502  # Input button released
#   SDL_INPUTWHEEL        = 0x503  # Input wheel motion
#   SDL_INPUTPROXIMITYIN  = 0x504  # Input pen entered proximity
#   SDL_INPUTPROXIMITYOUT = 0x505  # Input pen left proximity
#
#   # Joystick events
#   SDL_JOYAXISMOTION     = 0x600  # Joystick axis motion
#   SDL_JOYBALLMOTION     = 0x601  # Joystick trackball motion
#   SDL_JOYHATMOTION      = 0x602  # Joystick hat position change
#   SDL_JOYBUTTONDOWN     = 0x603  # Joystick button pressed
#   SDL_JOYBUTTONUP       = 0x604  # Joystick button released
#
#   # Touch events
#   SDL_FINGERDOWN        = 0x700
#   SDL_FINGERUP          = 0x701
#   SDL_FINGERMOTION      = 0x702
#   SDL_TOUCHBUTTONDOWN   = 0x703
#   SDL_TOUCHBUTTONUP     = 0x704
#
#   # Gesture events
#   SDL_DOLLARGESTURE     = 0x800
#   SDL_DOLLARRECORD      = 0x801
#   SDL_MULTIGESTURE      = 0x802
#
#   # Clipboard events
#   SDL_CLIPBOARDUPDATE   = 0x900  # The clipboard changed
#
#   # Obsolete events
#   SDL_EVENT_COMPAT1     =0x7000  # SDL 1.2 events for compatibility
#   SDL_EVENT_COMPAT2     =0x7001
#   SDL_EVENT_COMPAT3     =0x7002
#
#   # SDL_USEREVENT thru SDL_LASTEVENT are for your use
#   SDL_USEREVENT         =0x8000
#   SDL_LASTEVENT         =0xFFFF