For me its already too late; I bailed out a long time ago. Not towards Chrome but SeaMonkey. Still a Mozilla engine (which isn't bad at all IMO) but without the upgrade madness. However, I have been using MSIE9 more frequent as of late.
But onto ESR... I think its doomed to fail, and I'm not just saying because I'm not a believer. First of all; the ESR project is rather new. From what I can make of it (check the proposal on the Mozilla wiki) the base version is FF10 which was only released approx. 5 months ago. You can also clearly see the reasons behind it:
"The shift to a new release process has been difficult for organizations that deploy Firefox to their users in a managed environment. We've heard 2 primary concerns"
That new release process otoh has happened MUCH longer ago. Around FF5. So it took them 5 releases (which, I guess didn't take that long ;-) ) to finally realize that companies and more serious users actually got fed up with the speedy release dates and that this couldn't be maintained.
Something every regular user (myself included) could have told you up front. Heck, worse: most of us DID on fora such as El Reg. Guess this is the kind of attention we got: /none/.
Concluding from that I think its safe to say that this whole ESR contraption is nothing more than damage control. Too little too late? That I can't say, but I have very little faith in it. Why?
You see; it seems that the main thrive was to present a version ASAP which would be "Firefox" but without the "upgrade madness". Now I wonder: how much preparation went into this project ?
Because there is something Ubuntu LTS (Long Term Support) has clearly shown us... Maintaining such a project is relatively easy. Not saying its a piece of cake, DON'T get me wrong. But its doable.
But actually maintaining it in such ways where the user can easily upgrade (move) from one LTS version to the next has so far proven to be more than difficult. In fact, in my experience that upgrade has often been plain out impossible. You were better off with backing up your data, wiping your disk clean and re-install.
Sure; Firefox is a browser and not a whole OS, I see that. But I cannot help, considering the context I've pictured above, if it won't eventually fall right into the same trap as Ubuntu LTS has. What guarantees are there that upgrading ESR won't actually give even MORE headaches and issues than a regular browser ? Especially considering that the project is sort off brand new ?
Another aspect which would make me very weary on this... Didn't Mozilla state some months ago that they didn't really care for the Enterprise and wouldn't be targeting it ? In fact, I recall them saying this around FF5 when they started their new upgrade policy. Could it be that when they finally realized that it was actually seriously hurting their market share that they changed their course?
How could you not be skeptical about a long-termed project when the company behind it has already shown to produce very poor results when working out long term strategies ?
I know I'm a critic, but I don't see this working out.