Let's just do some math here.
The original lovely Sims games started up in...what? 1999? and the last one came out in 2003.
First generation: 5 years
The very successful Sims 2 came out in 2004 and lasted until 2008.
Second generation: 5 years
The piece of shit Sims 3 started in 2009 and has apparently a final release set for this year, 2013.
Third generation: 5 years
Naturally, it seems the 5-year contract has expired, so EA has set off to create another base game for a new generation of the Sims. set for release next year. The only good thing about this thus far is that the game won't require any internet access to play. For some that means no crappy SimCity, for others it better mean no goddamn glitches or patches to deal with.
Starting next year, we loyal Sim fans get to buy all the same expansion packs released for every generation all over again.
I think for now I'll pass on The Sims 3 University Life and Island Paradise and just stick with my currently moderately glitched everything else.