There have been several versions of the Sound Blaster Live! released since the line's introduction:
Eventually Creative Labs began releasing versions of some of these cards (the X-Gamer, MP3+, and Platinum) that supported Dolby Digital 5.1 surround sound (these can be identified from their predecessors by the inclusion of "5.1" at the end of their names). These models were slightly better than the previous ones but weren't much different. The main differences between the versions was what extras came with them. The X-Gamers came bundled with some popular games (which changed a bit as the years went by). The MP3+ models came loaded with software for creating and editing music. The Platinum model came with both software bundles, a control panel that fits into a 5.25 inch drive bay with various plugs and knobs on it for convenient connecting of other sound equipment (speaker systems, microphones, etc.), and a remote control. The "Value" variant has much less in terms of software but the card itself is no different.
The whole line is based on the EMU10K1 chip and has been a top of the line choice for non-professional (i.e. not in a recording studio) sound recording and playback for quite a few years. Recently Creative Labs has released the Audigy which is better than the Live!, though not by enough that Live! owners should go out and buy one expecting to be blown away by the improvements.