Underestimated, underappreciated, underdeveloped and underachieving. This MMO just needs a little love.
It's sci-fi... Finally! No orcs, no elves, no magic... and no F'ing gnomes. The writing is really cool. There's no "real world" experience - when you log in, you choose which "hardline", or phone booth, you want to rez in front of, and then you appear in a world that slowly transitions from streaming green code into gritty urban textures. All the buildings are fully-modeled buildings and not just box-shaped landscaping. You can climb water pipes and fire escapes or run into buildings through the front door and dash out the exit. The hardlines and the subways create a decent public transportation system with quick load times. The missions, though atypical MMO quests of killing npcs, escorting npcs, delivering items and/or conversing with npcs, are scripted and presented in a reasonable, semi-convincing fashion (as opposed to fetching an orc's butt-scratching stick or wasting scores of pigs for the hell of it). There's a strong RP community on the Syntax server, and Sony has gone with the flow. There are weekly players events at different landmarks for trading, teaming up, and hanging out. There's also several nightclubs for hosting rp events and some sort of in-game streaming audio service that allows players to enter URLs, which has spawned a community of third party MxO "radio stations" and in-game DJs.
By far the best thing about MxO is character management. As a character levels, the player distributes bonus points to stats at will, and the character's level determines its maximum skill points and "memory capacity". After that, the player acquires and increases all skills with currency collected from dead baddies and builds the character's spec by downloading the skills from the Operator through a hardline... Though most of this sounds Greek, the bottom line is that a player can re-spec his character on the fly. If I met a group of players and they say, "We're looking for one more, we already have a healer and dps... Can you tank?", then I can go to nearest hardline, call the Operator and switch up my programs from dual-wielding submachineguns to hand-to-hand combat. "Woah... I know kung-fu!"
In the negative column... I feel like Sony gave up on this game quick. There doesn't seem to be much added to the game's content since it's initial release, though there seems to be great strides made in improving server stability and lag reduction. The graphics, both in-game and cut-scenes, are noticibly dated. Occassionally, I'll run into a broken quest or a glitched NPC... But the worst problem is a lack of new players. Most people don't even remember this MMO is still around, and what few remember it are still convinced it's a bad game with no growth. Easily 90% of the characters I see are at max level, and I get the feeling that the only way to find characters my level to team with will be to join a guild.