This survey was done by Vic Ferreira et al at the Center for Research in Language, University of California, San Diego. There were 187 responses, but one was unanalyzable (the respondent did not specify a software package).
Summary of the survey results
E-Prime is the most popular package of those surveyed, but the majority of folks are using either E-Prime, DMDX, or some flavor of PsyScope. E-Prime, PsyScope, SuperLab, and ERTS are all rated as easy to build experiments with, and about equally so. DMDX and NESU are seen as slightly harder. Presentation and MatLab are notably the hardest of the commonly used packages. SuperLab was seen as easiest for novices. E-Prime and PsyScope were rated a shade harder for novices, and then from ERTS to SuperLab Pro to DMDX to NESU, novice-ease ratings dropped. Presentation and MatLab were both seen as notably difficult for novices. DMDX nets the highest satisfaction rating, with PsyScope X and E-Prime a smidge lower. MatLab, SuperLab, and Presentation rank below that, ending with NESU, PsyScope classic, and SuperLab Pro. PsyScope X has the highest "sticking with" rate, and E-Prime, SuperLab, MatLab, and DMDX all have 50%+ "sticking with" ratings. People are running away from PsyScope classic, probably because the classic Mac OS is very quickly approaching end-of-life. E-Prime, both flavors of PsyScope, and DMDX are highly recommended. MatLab is also well recommended. Then it drops noticeably to Presentation, SuperLab, ERTS, and finally SuperLab Pro and NESU. A summary of two open-ended questions is also included below.
Of the 186 valid responses, the most commonly used software package ended up being E-Prime (57 responses, 30.6%). Here's the ranking of software packages, listing number of respondents and percentage for each: