This is not full review of Lion, but just my initial look. I downloaded Lion as soon as it became available in the Mac App Store. I know that some of you are saying you should have waited, but when it comes to OS I like to live dangerously and try the newest thing when it becomes available. It took about 55 minutes to download, there was one glitch when it stopped downloading and said please try again, I hit resume and both the download and my heart restarted. Once it finishes downloading it then starts the install process. At this point you have to agree to the EULA and fill in your user id and password. The installation itself takes about 35 minutes, once it is done the computer restarts. Clearly this not something you want to do if you are in a hurry.
At this point click on the Assistant Icon in the Dock, you can read about gestures, at the bottom of the text it will say continue to Lion, click on that. At that point the OS will tell you if you have any applications that are not Lion compatible and move them to a special folder. I had one, TotalFinder which fortunately I don’t use. At this point Lion starts up. The first thing I did was go into Magic Trackpad in System Preferences and check what gestures were available, you can uncheck the ones you don’t want. If you use a mouse, then go to the mouse icon under system preferences. While doing this I determined that Lion makes the MagicPref app I had installed to use with [Snow Leopard](http://www.apple.com/macosx/snow leopard) unnecessary. Opening up. Apple Mail also lead to another discovery, many third-party add ons may not be ready for Lion. I have both Mailtags and Mail Act-On installed, neither of them show up in Apple Mail under Lion. Mail Act-on does have a prerelease version you can download. If you have a favorite add-on you may want to check to see if it is ready for Lion, before installing Lion. Another thing I noticed right away was in the upper right hand corner in the menu, was my user name. Now you can easily switch users, this is great if you have multiple users using the same computer. The finder window also allows you to view your files, folder and application how you want including by category. This can be quite helpful if you have a lot of applications or files and folders.
Do you need to download Lion right away, no there is no reason to be in a hurry. Is there any major reason to wait (other than application and add-on incompatibility) I say no. The final decision is up to you, do the research and make the best decision based on your circumstances. As for me I am happy I installed Lion. How about you have you installed it, what do you think. If you haven’t installed it and you are on a Mac why not?