As some of you know I mainly do landscapes for myself and I used to upgrade every other PSCS cycle. I am currently at CS5. Since I am happy with CNX2 as a raw converter and Windows as a DAM - and I am not planning to start using LR - I figure my PS costs averaged out at around $5/month for the last several years.
I used to upgrade every 2-3 PS updates but took every Lightroom update. Even before CC, they stopped the ability to upgrade other than the latest Photoshop, so I'd stopped at CS5 like you.
But for me, even if I could update every other PS CSx release (perhaps every 3 years) and every LR update (every 18 months or so) then the cost would be about the same as the Photoshop CC package. In UK prices, just over £100 per year. The fact that I use Lightroom (and update that every time) probably tips the balance for me.
Given that this is a time-limited offer, I've gone ahead with it. I don't like renting software. What happens when they lose credit card details (like last week) and I have to get a new card? If I don't update my card details online by the next billing cycle, my software gets switched off. But I've still got my CS5 licence and an LR5 licence for that, or if I change my mind after a year.
The current time-limited $9.99/month offer for CC+LR is twice my historical cost - but low enough that I could grin and bear it. The question then becomes whether there is an actual reason for me to buy into CC.
In other words, are there any compelling features that would make a photographer want to upgrade to CC from CS5/6? Shake reduction and new/improved Smart Sharpen are neither here nor there to me, so I can't say I see anything that appears like a must-have feature that I don't already have (perhaps through a plug-in or third party software). But maybe I'm missing something. What was the killer feature that made you take the plunge?
In terms of features probably not. There's not much new that's useful to me in CS6 or CC over CS5.
Or is this really like Word 2007 and 2010 - the difference in functionality between the two is so limited as to appear immaterial to most people?
Oddly, I thought the Office 2010 update was useful. Microsoft seem to alternate good and bad releases of software; they introduce something half-baked, and sort it out next release. Office 2007 introduced the ribbon interface. I don't much like that, but more to the point they did it badly. Office 2010 has few new features, but gets the ribbon sorted out better. Office 2013 appears to be a waste of space for most people.
So you get:
Office 2000: good
Office XP: bad
Office 2003: good
Office 2007: bad
Office 2010: good
Office 2013: bad
Windows XP: good
Windows Vista: bad
Windows 7: good
Windowss 8: bad