In relation to my post "Please share your thoughts on this: 1000D to 2nd-hand 50D", I was pondering in getting the 24-105 until the 17-55 suggestion came up. I've gone crazy over the past few days on which one to get. I just want to thank everyone for their input in helping me out pick the lens that I would get. After considering Daniel, Braden, Jan, John, and David's suggestions and alternative options, I swallowed my pride and got myself a Sigma 17-50 2.8 to upgrade my defective kit lens (AF broke down and been using it for awhile in manual focus mode) and also got the Canon 85mm 1.8 (to fill-in my hunger for extra reach and for portraiture sessions).
Passed up in getting the 50D too and retained my bond with my beloved 1000D/XS body. The Sigma 17-50 seems to par with Canon's 17-55 in reviews and it's about a third cheaper though 5mm shorter which I think is quite insignificant. I just got the two lens tonight and I can't wait to test and try it on in actual shooting tomorrow. []
By the way, I still got some change on my budget for initially planning to get the 24-105, and also got myself a better camera bag -- Lowepro's Fastpack 200.
Thank you again everyone for all the input and suggestions.