I think the worst thing that you can do is compare this game to The Sims 2, as they are nothing alike, they are both brilliant in their own different ways.
At first I wasn't impressed with the game, as I felt like it was lacking in aspects. However, after a day on and off the game I really got into it. For instance, the life cycle is a lot more realistic as you have toddlers for 7 days etc. Another great aspect is that you don't have to constantly rely on making endless friends to progress in a career, but rather get extra little tasks to do round town if you wish and do "extra credit" activities such as making homecalls if you are a doctor out of hours. At the start I found the seamless loading screens unimpressive as I personally didn't find them a big problem in The Sims 2. However, as relationships with other Sims progress, your family becomes larger, your career becomes more important, and "visiting the spa" after work becomes something to pass the time, the convenience really becomes evident.
I've read a lot of reviews of people complaining about the game not working. It is obvious that all of The Sims games have been demanding for your computer to run, but I've never really "stuck to the rules" within requirements. I didn't check mine, but I just know that I have a laptop of decent quality and with Windows 7, and it works like a dream. If you are expecting to run this game from an old laptop or PC then expect to be disappointed.
In conclusion, I would highly recommend this game, not to compare it to previous Sims, but to have a go at something else, and have fun with something different.