If you want to learn programming, a Lusternia-style MUD is not the easiest way. I'd try creating a text-based single player game first, to get the basics of parser-writing, etc. Try to create a cool Infocom game or a text-based RPG before trying to do the multi-user thing.

Ruby is consider the "cool" language because of the Rails library and the syntax of Ruby, but its an interpreted language which is always slower. Ruby on Rails is used by a lot of Web 2.0 projects, but scalability issues still need to be resolved. Ruby's still too new. Also, Joel Spolsky has some great articles explaining why too much abstraction makes you weak.

http://www.joelonsoftware.com/articles/Lea...stractions.html
http://www.joelonsoftware.com/articles/LordPalmerston.html
http://www.joelonsoftware.com/articles/The...avaSchools.html

All the IRE muds had the benefit of a CTO Christopher Kohnert, a gent who has a Masters Degree in Computer Science and wrote the rapture compiler. Writing an actual practical compiler is difficult work. That's a hard skill to beat.

Yeah SMAUG and LPC are probably better bets.

ALthough most other muds have... not sure what you call it.. but you and target attack at same time.. IRE's have eq and bal limiters and enemy speed is variable.