are you doing something to get the ranking to jump. There are a few methods to do it...could you share how you have ?
i think you should get quality traffic from(us, uk, canada ...) But really alexa has got interesting algorithm
Alexa ranking may be an inaccurate picture of the actual traffic to your site because i believe it is accumulated only from people who surf the web using the Alexa toolbar which is for IE. Your ranking will increase quickly if you recieve good number of visitors everyday, if you get visitors from varied sources rather than one consolidated source. If the number of pageviews for your site is very good. This can offset even a low traffic and reach to increase your rank.
Well to get visitors from varied sources is a tough task....i have actually cheated this method and got few sites Alexa's ranking to jump. Yes Alexa's ranking gives an inaccurate picture, however there are many ppl. out there who value sites based on Alexa ranking and Google PR.