I checked out SUMo many years ago but the "security alert" hairs on the back of my neck started vibrating. I remember it being a good program in terms of functionality, look and feel. But I didn't (and still don't) like the idea of a 3rd party program having a full inventory of all the software installed on my computer, or that it regularly checks to make sure it is all current. I personally have nothing to hide (other than my personal information, etc.) but not the point. Others might and I do have clients who have very sensitive customer information, for example, in programs they use for their businesses.
The concept is great. And based on KC Softwares other programs (like Startup Sentinel), I trusted the company to not do anything nefarious. But considering how frequently and successful the bad guys are hacking into organization's networks (see
this), I didn't, and don't feel comfortable using SUMo, or recommending it or similar programs - especially when most software either auto checks, or has a simple menu option to check for updates making it easy to keep our installed software updated anyway.
Still, in this case, according to their site, the entire KC Softwares company is, or rather has closed its door. And sadly, they have offered no explanation. We consumers need these small developers to fill various niche markets. I personally don't want Symantec/Norton or the ilk scooping them up then ruining the program, or just driving them out of business - as they so often do with their [perceived?] competition.
We can only hope the developer has decided it was time to retire, lay back in the sun with a frosty margarita in hand, and simply enjoy the fruits of his labor.