I've been waiting until after the summer to write an entry like this, but I just think it should be said: If you're new to Switzerland, you owe it to yourself to get a General Abonnement. If you live in a town, especially in a city, you owe it to yourself to get a GA far more than to get yourself a car.
A car's just a pain in the backside most of the time, unless you really want one because, say, you just love driving (which is fine). It'll cost you 150 francs or so per month just to park it in a lot of places, plus a couple of thousand francs or more per year to insure it, fuel costs, expensive parking in town, assorted inspections, and so on. Sure, but everyone just needs a car from time to time, right? Absolutely! In that case, a Mobility subscription will take care of those occasional trips where your own vehicle is necessary.
But propaganda aside, why is a GA such a great thing to have? It's expensive, right?
Yes, when you look at the purchase price (Sfr. 3100 in second class, SFr. 4800 in first) you are likely to experience a bit of sticker shock, But let's do a comparison with the UK. An annual second class season, Oxford to London (only the train - no Tube at the other end) - will set you back £3996. Even at today's dire exchange rate that's SFr. 6600. As a frame of reference, Oxford to London is about the same distance as Zürich to Bern - and about the same time on the train, just under an hour.
So, for less than half the price of that season ticket, you can get an annual pass for pretty much every form of public transport in Switzerland, or at least all the bits of it as outlined on this map. Virtually all rail routes (with a few exceptions such as the Jungfraubahn), buses, trams, lake shipping, all wide open. Suddenly decide to go to Geneva? Just get on the next train. Day trip to Ticino? Sure. Want to do a scenic round trip over the Oberalp pass? Why not? Trip out to Konstanz and a cruise along Lake Constance? All inclusive. Your work commute? All part of the deal.
The real win, though, is that with a GA you can see the beautiful country that is Switzerland without even really thinking about it or worrying about the price. I haven't been keeping detailed logs of the trips I've made over the summer, but I'm pretty sure I've seen an awful lot more of the country than I would have seen had I been having to pay out for individual tickets. As a recently-arrived expat this is a real joy, as it's given us the flexibility to go off exploring on a whim.
A nice side bonus if you're bourgeois enough to have a first class GA and frequent Zürich Hauptbahnhof is that the SBB has a nice lounge there for first class GA-holders (plus one guest!) where you can hide and drink coffee until your train goes.
Oh, and if there are more than one of you in your household, there's a hefty discount on GAs for additional members of your family. And like a halbtax, it gives you 25% off on border-crossing trips into neighbouring countries. One top tip - if you want to spend a day in Germany exploring the Black Forest, simply use your GA to get to Basel Bad. (remember, it's valid on the ICE from Zürich) and buy a Baden-Württemberg-Ticket from the DB ticket machines. Up to 5 people, valid all day on non-InterCity trains and the vast majority of buses, trams, and so on in the state of Baden-Württemberg. All for €28, or €19 for the 'single' version if you're travelling by yourself. Bargain!
So certainly if you're new to Switzerland (and even if you've been here a while), I can highly recommend taking a good look at the GA. It solves a lot of problems in one go, it lets you see the country and go off on random trips without having to even think about it, and it's pretty much the best public transport bargain out there.