The best replacement for x10 is insteon.

The best alternatives to x10 are rated as following:
★★★★★  insteon
★★  x100
★★  x20
★★  z wave
★★  x10 pro
★★  z-wave
★  captivate
★  upb
★  10x
★  lx7
★  x11
★  wemo
★  lx5
★  x10 mini
★  xcalibur
★  lightwaverf
★  x100 fuji
  x05
  zigbee
  n8
  s95
  nano pro
  rx100
  direct x9
  arc
  samsung captivate
  cbus
  zwave
  x10 mini pro
  g15
  x-10
  canon g12
  galaxy s
  x8
  x10i
  s100
  xf1
  x10pro
  g12
  n900
  satio
  htc hd2
  lutron
  xperia arc
  fuji x100
  htc desire
  upd
  c-bus
  xt720
  canon g15
  s110
  canon g1x
  x9
  nikon p7100
  nexus one

Your alternative for x10 is not listed? Suggest!
Speaking about x10, one probably shouldn't forget about cfl bulbs.

Other search terms related to x10 and their ratings are:
★★★★★ cfl bulbs
★★★ vera
★★★ insteon hub
★★ homelink
★ ademco
You have in mind a companion for x10 and it is not yet here? Propose!



Google Trends

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x10
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