After playing this for the past two weekends, I figured I'd give a review of what I thought about Lego Universe since it's official release is this week.
First off this plays almost exactly like the other more recent Lego games do, minus the theme specific abilities & mechanics. While I've only played Lego Star Wars(PS3), I immediately noticed the similarities between the 2. Just like Lego Star Wars, LU keeps the complexity of the game play to a bare minimum. This might not please the more hardcore gamers, but it makes it perfect for the target age range. There are 3 numbers that are important for just about everything. They are your HP, your armor points and your Imagination. HP & armor are what is used to keep you alive. Armor is used up 1st, following your HP. Imagination is how you power all your abilities. All three are collected as drops from anything you smash or build.
LU has 3 different build methods. The 1st is quick build, which is just like what you'd find in Lego Star Wars, where there is a set of bouncing bricks that you quickly throw together to make some predetermined object. Each quick build takes up a certain amount of imagination to build. The 2nd is modular build and is used primarily to build things that you'll end up keeping & using later(ie racecar & rocket ship). For this you need certain prebuild items, that are place in a mold of sorts. Finally, is free build, but as far as I can tell this is only used in your personal properties(I haven't spent much time there yet).
I'd rather play LU on a console than on the PC, especially since at the moment I haven't noticed any need to "chat" with others in the game. Also, unlike other RPGs, there doesn't seem to be any need to get into a group, unless you want to go around with a friend or two. So far, I've only come across one instance where a group is needed, and it's at the very end in an instance that is reminiscent of a MMORPG raid, but for a much smaller group. And for that, if you don't join with friends, the game allows you to wait for others to join.
One of the things that impressed me was the level of care given to the moderation. Everything is moderated, right down to the models you build. There are even a white(accepted) and black(unacceptable) phrase lists employed to make sure that questions like "where do you live?" or more dangerous things asked/done in normal chat. There is a way around the moderation, but only if you both agree to be "best friends", something that they suggest you reserve for those you know outside of the game. This moderation should alleviate most parent's concerns about letting their children play in an online game.
At the present, the game is VERY small. There are only 3 "outdoor" areas, and take no time at all to explore once you progress high enough to not die too quickly. Each area is about the size of a typical Lego Star Wars area, which considering the 1st one had 18(6 areas for the 3 movies) areas, this game is a whole lot smaller. There are various reasons to stick around in an area, but I found that each area took about 2-3hrs to fully explore & get about 75% of the quests(or missions as they are called in LU) done. Add another hour to try to get the hidden items that give your character permanent power ups.
One thing that does keep me coming back(besides the RPG obsession of getting EVERYTHING) are the minigames. Each area has different minigames, specific to that area. For example, the pirate area has a game of shooting down enemy ships & monsters from a cannon on the "good" pirate's ship. There are at least 2 race tracks(there might be another in the last area that I'm not done exploring). But unlike Lego Racers, each car has the same stats. This does make it nice, since more hardcore players would be able to dominate each race by just being able to find/buy/quest better car parts.
I haven't spent much time building up my personal areas yet. I have tinkered with their behavior thingy that allows you to make your area do something other than look pretty, but not enough to give a good opinion of it. Like the rest of LU, it's very simplistic, and so should be very easy to use once you figure out the proper order of things.
All in All, I think Lego Universe is good for what it is. It will never compete with the more established MMORPGs, but I think that's a good thing. It should be fun to get away from everything & just have fun. Which is something that's very hard to do in other MMOs. If I was a parent I know I'd especially like that there's a game I could play with my children and not have to worry about other less-honorable people ruining the experience.
It's Lego('nuf said)
Fun without complexity or feeling like work
Annoying to try to jump with a keyboard & mouse
Still a bit laggy
No real grouping or social aspect