How quickly will I improve?

Impossible to say. You appear to have lost a good deal of weight in a short period, congratulations!

The rest depends on the training schedule you follow, how well your body adapts, natural talent, many things that just can't be quantified.

John 

too many variables to consider to know or give you a correct answer. It will depend on your training load (how much), genes, background, current fitness, etc. In general it can take around 6-8 weeks for your body to adapt to certain load and achieve the gains from it. Less trained individuals can realize greater gains in shorter perdiod of time with just consistent training while more trained individuals will require greater loads and time.

keep on training, be consistent, smart and let the work let you know how much you are progressing and how far you are or not from your goals

Train consistently and you'll improve.  Move your improvement time horizon from weeks to years and let the training become a lifestyle.  Each year you'll be in better shape and you'll be able to handle more training.  Take pride in the little things you notice - a hill that used to be hard isn't so hard anymore, that run which used to be long becomes a a warm-up, pants that are too loose, etc.  Don't worry about where you place in races; by training consistently and eating right you're guaranteed to improve.

How you place relative to others depends on a number of factors you can't control, including how many years of training you've already completed, genetics, etc.  It's common to see some people become fast in their first year or two, and it's common to see some people become fit but never particularly fast.  If you're the competitive type you'll likely become faster more quickly than many others.

FWIW, a little over two years ago I finished 24 of 27 in my AG in my first tri.  Now I expect to finish in the top 20%, sometimes top 10%, in my AG.

Brian

man I hate men.

25lbs in 6 weeks?? sheesh.

Like others have said to many variables.

This is my 6th year in and I'm still not MOP, even with consistent training with coach for last 5 of them. My genes, age and beinga women makes it unlikely. 

Why care where you are compared to the pack? Really you compete against yourself. Try to do the best you can each day in each training session and every race. Enjoy the journey..have fun!

I would have to agree with what the others have said. 

Like you, I have lost a lot weight in a short period of time, 49 lbs/10weeks.  The weight loss is significant, but the performance gains take lots of time.

If you want to be successful, and success is relative, time and consistant training are your only friends.  Little gains are just as important, as big ones.  Enjoy the little gains, for they are gains, and they do add up.

kevin

You are not really asking about improvement, but placement in races.  You will improve your fitness the more you exercise and teh more you SBR, the better you will SBR.  I have knocked off 20-30" on my 100/yrd swim time over the past year and 5+ minutes off my 5K PR but I will likely be MOP in most races.  Have I improved?  absolutely.  But I will not likely place any better.  The conventional wisdom is that with concerted training efforts you should see good fitness improvement for the first 2 years or so of training, then you will reach a plateau and will need to be more particularized about your training. As for race result, as many will tell you, you never know who will show up.  If it is you and 100 pros, you'll likley finish last even if you PR in every leg.

Prepare like you want to win and you have the possibility of doing so.  The definition of "win" is what you need to work on.  For me, that is meeting certain goals, not actually winning, which, due to inexperience, age, genetics, lack of training time, etc. will never happen.