
Job descriptions in ID (or, ISD) these days are all over the map, with very little consistency. It doesn't help that few HR and Recruiters have any knowledge of, or experience with, the field. So I'm going to propose some roles as I understand them, in the hopes that some day hiring managers will be able to articulate better what they want/need in terms of talent for their training departments or projects.
Note that one person can hold multiple roles. These are ROLES not PEOPLE. And most of the time these terms are not used with any degree of rigor or standardization. So don't get offended, but please do share your suggestions and feedback!

Instructional Designer
Capable of performing or at least managing entire ADDIE process. Primarily responsible for translating raw content into instructional content. In the ADDIE process, this means Analysis and Design: interacting with SME, defining Learning Objectives, and writing storyboards or scripts. Additionally, IDs will be responsible for Evaluation planning and review, providing that is part of the project.

Instructional Systems Designer
While this role is often used interchangeably with Instructional Designer, I think there should be some, albeit subtle, distinction. If the term "Systems" has any meaning, it should define the scope of design to be larger than a single course, involving curriculum planning and delivery/tracking information systems such as LMSs. If you need to develop new technologies, processes and templates, not just new courses, you are working on a Systems level. However, if you just need someone to turn out another course in your existing system, you would be looking for the Instructional Designer/Developer roles. This role will be most active in the Analysis, Implementation, and Evaluation phases, but would also have significant input in high-level Design and Development tools and processes. Generally this role should be strong with IT concepts as well as learning management strategies. This could be your one person training department, doing the whole thing, but even for a small organization that's a lot of ground to cover.

Instructional (Multimedia) Developer
Expert in one or more learning development and web/multimedia tools, comfortably moving between tools or learning new ones with ease (except perhaps Flash and Actionscripting, which are specialties in themselves). They are primarily responsible for creating the actual learning materials, perhaps from a storyboard or other content that has been processed by an Instructional Designer in the Analysis and Design phases. Strong graphic design skills/talents are helpful here, or you may need a Graphic Designer. In the ADDIE process they will be most active in the Development and Implementation phase. So if you need a course created from soup to nuts, you may actually need an Instructional Designer/Developer.
Instructional Technologist
This role is less commonly found. But if the term "technologist" has meaning, it is someone who uses or applies technology and existing processes to a problem (as in "medical technologist"). They may serve as Instructional Developers, but perhaps without the Graphic Design/Multimedia skills or Instructional Design background. They may operate or maintain instructional systems designed by the ISD, but you wouldn't expect them to create a new system.

Instructional Systems Developer
This is what I would call someone who can program a learning portal, LMS, or CMS, or at least can develop custom code to interface with such things. They'll need to know SCORM/AICC and whatever languages are required by your particular environment (.NET, Java, PHP, etc.). These folks are not Developing the courses, but are creating the environment in which students take the courses. Systems Developers (and Analysts) will want to follow software development processes (like RUP) instead of ADDIE.
Instructional Systems Analyst
This is also a rare beast. This would be someone who operates, diagnoses, and repairs ("optimizes") Instructional Systems, typically enterprise software like LMSs, CMSs, etc. These folks will be heavily involved in the Implementation phase, as that's when all the data begins hitting the servers.

Trainer/Training Specialist (anything with the term "Train")
These are your classroom and virtual classroom instructors. They are the extroverts who excel at going in front of people, creating an engaging atmosphere, and teaching synchronously. They adapt their lessons on the fly to changing content and audiences, and travel to various places. People in this role may be involved in the complete ADDIE process, as they are directly in contact with the students, but will generally not be involved with self-paced learning development, unless they are Instructional Designer/Trainers. [That said, I think the title "Training Specialist" as used in the wild is often a holdover from pre-ID days, with the meaning, "HR person who helps employees learn stuff." But they're probably an ID.]
eLearning/Multimedia Project Manager
"A good eLearning project manager needs to understand what makes good eLearning, so they can make decisions that positively affect the quality of the product, and leverage the talents of the project team. [...] Some organizations have split the PM role, so that instructional designers manage the project team while a PM only manages the schedule and budget." - Bob Elmore via comment on eLearning Guild LinkedIn Group:
http://snurl.com/jvlft
Let me reiterate, before you get your nose out of joint or start rewriting your resume: one person can hold multiple roles. These are ROLES not PEOPLE. And most of the time these terms are not used with any degree of rigor or standardization. So don't get offended, but please do share your suggestions and feedback!
(Role info-graphic from http://rebirthofreason.com/Articles/Setzer/Experiencing_Objectivism_through_the_Enhanced_Tri-Quation.shtml - don't ask me, I just liked it!)