This bit is the problem. I don't jailbreak a device before I am ready to throw it away. I've seen too many issues with non-official hacks of various sorts. Nothing major; just rough edges.
They even provide an official tool for rooting.
There's pretty much no chance of bricking your phone, and if you go with a stable CM build, you shouldn't have any problems.
http://get.cm/?device=i9300&type=stable
... while the Galaxy Nexus has already gotten its OTA update. Closest I've found is the SuperNexus ROM, but even that's still glitchy.
I'll probably buy my first Android device when they do. As a long-time iPhone user, the Android device market has been utterly bewildering to me. It took me a while to discover that the Nexus handsets were the only ones that (a) offered the naked/unskinned Android experience and (b) received Android updates from Google directly independent of network provider schedules (I think?).
Allowing handset manufacturers to skin the Android UI and bolt on their own wacky additions, then letting carriers determine when updates are provided has diluted and confused the Android handset marketplace, in my opinion. As an end-user, it is not just a choice between hardware; I also have to work out which manufacturer has 'reinterpreted' the Android UI, and which carrier will let me update the phone. (And I still haven't worked out how OS updates work if I buy a second-hand device off contract.) It can be wonderful to have such choice, but the Android phone market is far more confusing than the iPhone one.
[1]: http://www.theverge.com/2012/5/15/3022682/google-direct-sale...
With Apple it's likely less of an issue considering they have an impressive profit margin on their products and a strong lock on their target market. If the recently announced iPhone doesn't sound too impressive the customers are still likely to buy it as they're unlikely to consider other alternatives as an interim.
As mac user, I feel like they have a strong lock on me. Since product releases are infrequent and I wil own it for 4-5 years, I hesitate when buying a new one (I don't want to start 18 months behind).
Androids move fast enough that buying a new one you are guaranteed to find yourself a few months behind within a few months. But, it will only be a few months.
And the iPhone releases are not always exactly 12 months apart from each other as well, right?