It was a great place to work but hasn't been the same since the buyout
Pros
OpenMarket has(/had) an amazing group of smart and talented people. The org charge was very compressed with very little "middle management" layer. You could talk directly to the president and get straight answers if you wanted them. The company's overall communication _was_ great. I felt like I knew what our direction was, how our financials were looking, what our competitors were doing, and how we were planning on changing to meet new challenges. Benefits are above average, pay is good, and the work/life balance is fair.
Cons
The new parent company broke trust by promising that everyone would have a place at the combined company, and then laying-off part of the engineering staff. That was followed by several other communication and policy blunders that caused many very talented people to leave. Infobip seems to realize they have a retention problem. They acknowledge their mistakes, but there still hasn't been any fundamental change to how they communicate and interact with the OpenMarket people. The C-suite keeps talking about how we are going to be integrated into a single company, but that vision doesn't seem to trickling down to the individual departments. It is now a year after the buyout and my department still has no idea what our roll will be and still doesn't have any regular communication with our counterparts at Infobip. Instead we get a constant stream of last minute demands for integration work in order to move all of OpenMarket's customers over to Infobip's systems. Despite their (already broken) promises of a merged company where everyone has a job, it still feels like we are being sucked dry and will then be discarded. The amount of OpenMarket people leaving and walking away from retention and end of year bonuses is crazy. In response, there have been several new perks announced, including some additional vacation time, and other improvements in benefits. There still hasn't been any change to how Infobip is handling the cultural, communication, and trust issues though.