Congratulations! I think implants are a wonderful idea and you're lucky that the condition of your mouth and jaw allows you to be eligible for them. I don't have implants but know many people who have them, ranging from young people who lost adult teeth while playing sports, in accidents or goofing around to older people too vain to accept dentures.
The procedure is lengthy and begins with preparing your jaw for the implants. The dentist drills a hole into your jaw and inserts the implant screw while you're under anesthesia. He caps (crowns) this off and several months later replaces the temporary caps or crowns with permanent ones. The temporary crowns allow the gum to grow and heal and all sorts of stuff I don't remember/understand. I think the time period generally runs around six months between inserting the implant screw and placing the permanent crown, but am sure it fluctuates according to the patient. I believe that the only pain involved is for a short period during the healing process after the screws are placed.
I have no idea whether your speech will be affected because you're having this procedure done for different reasons than those of the people I know, but their speech wasn't affected in any way and I can't offhand think of a reason why your's should be further affected.
Here's a Wikipedia article about implants that you might find informative. Wiki isn't always 100% accurate (anyone can post and anyone can edit and it may take a while before errors are corrected) but it gives good general information.Dental Implants
Let's us know of your progress! I understand that the procedure is very successful.