Second Life vs. IMVU

I'm going to compare these two environments based on my own experience. Pros and cons of both worlds.

Second Life

Advantages over IMVU:

• A lot better graphics, more about it below.
• Close to realistic sky with clouds, fog, sunrise, sunset, Moon, stars.
• Time -- the Sun moves like in real world.
• Objects (avatars, avatar body parts and hair, trees, buildings, etc.) cast shadows on themselves and on the ground, lignt provided by the Sun, Moon or local light sources.
• Realistic light sources with diminishing light (light falloff).
• Realistic water with reflections, glitter, waves, real water effects, also from underwater.
• Realistic glass panels (walls, windows) that look like real glass.
• Reflective or shiny surfaces (metal, glass, shiny plastic).
• It is a big world, not like separate chat rooms. You can teleport from place to place using landmarks (bookmarks), coordinates, place names, map.
• Avatars walk, run, fly, jump, duck, swim, and you can see from the 1st person view -- look down and you can see your boobs (if female) and legs. Very similar to PC games where you walk and set your direction with your mouse.
• Camera controls are very flexible and convenient, at first it can be hard to get used to.
• You can customize your avatar anywhere. You can change the shape of all body parts using simple sliders.
• Avatar hair moves realistically.
• Avatar looks like a human rather than a doll. Skin textures are much more defined.
• You can speak (using a microphone) with other people, and your avatar's mouth is moving when you speak. Your voice will come from your avatar's direction. Voice is louder near talking avatar and gets quieter when you move away.
• You can adjust avatar accessories, shoes, clothes, hair to match your avatar's body parts and size while wearing them, and these settings will be saved automatically so you don't have to start adjusting again next time you wear the same items.
• Creators don't need opacity maps.
• Nothing similar to IMVU's Access Pass (AP) needed.
• No premium (VIP) membership required in order to create.
• No credit pend.
• Creators collect the profits instantaneously after purchase. 100% profits if product is sold inworld, and -5% fee if sold on the Marketplace (on website).
• Shops and malls are in-world -- you can walk around and buy stuff like in real world. You can also browse the marketplace on the website.
• Invisible online status -- great privacy! Your friends don't see you online and they can't bother you with chats and teleport offers. Extra great feature if you're a creator.
• Huge amount of settings (graphics, sound, camera, world, etc.).
• You can delete (remove permanently) unwanted stuff from your inventory.
• 3D image runs smoother (only in low poly areas, also depends on your hardware).
• Creating: no peer review, your products will be available immediately.
• Decorating is awesome -- you can see a nice grid on the ground, snap to grid, snap to angle, snap to size, etc.
• Clothing can be layered. Something you can never do on IMVU (having a 2-layer clothing -- mesh and body -- is not the same.)
• You can attach anything to any body part just by choosing from the attach menu. Cool eh?
• You can build anything anywhere (but the place must be set "build: on" for you) and take it and attach to your avatar if you wish. Can do super silly and hilarious stuff like that.
• Gifting your own creations (or others if they are transferable) is totally free -- you don't have to buy the item from yourself to give it to someone else.

Cons:

• Can be much more expensive if you really want to play and shop a lot.
• Requires a powerful computer with a good video card.
• Very confusing at first.
• My personal opinion: avatar shoulders, arms and legs have ugly shape compared to that of IMVU's.

IMVU

Advantages over Second Life:

• Much easier to start using it.
• Requires less powerful computer.
• Very easy to use avatar actions.
  (Dry hug, yay!)
• Posing spots are very easy to use.
• Creators: editing a product (e.g. replacing textures) doesn't cost anything.

Cons:

• The place is infested with texture and mesh thieves.
• It's too easy to rip off hardworking creators by stealing their work.
• Avatars can't walk freely, you must "jump" around on predefined dots.
• Graphics and related features are highly outdated, something we saw in late 1990's.
• Access Pass is required in order to see and use naughty stuff, and even then it's highly limited!
• VIP subscription is required if you want to create products.
• Creators: IMVU takes 10% + derivation fee off each product sale you make. Not quite profitable.
• Creators get often banned for unclear reasons, and thieves can continue stealing for a long time, sometimes forever.
• Creators' tiers system.