Going that route, I'd suggest 'date of oldest comment scraped so far' instead of/as well as the count.
I combined the above suggestions. While it is scraping the data, it now also has a table showing the last scraped elements posted date, the number of items scraped and the scraped score. This is split into two rows one for comments and one for posts.
As a learning exercise, I wrote a web app which shows some charts on your karma score.
I recommend just going to the website and trying it out, but here is a description of it as well if you're interested. To use it just enter your user id in the text box at the top and then press the go button. It will show that it is loading and after a while five charts will be shown.
Please note that it may take a while to load. I am scraping all the information from your users page. It shouldn't take too long though. On my computer it takes less than a minute to load all the information on my karma score, but it did take around half an hour to load Eliezer_Yudkowsky's karma information. YMMV depending on what computer you are using. It is not your score that determines how long it will take, but the amount of comments and posts that you have made. I recommend using chrome as I haven't tested it in any other browsers.
The karma calculated by LessWrong also might be slightly different to what my web app shows. For example, my webapp shows Eliezers karma total score as 290096 and in LessWrong it is 290174. I am pretty sure that my code is right since I counted one example out and I do know of one bug in the LessWrong code that would effect the total score. There are also other things that LessWrong takes into account that I don't, e.g. karma awards and the troll tax. The difference shouldn't be too major, though, so it shouldn't be a big problem.
The website is hosted on github and the code can be found here.
TLDR: Try out the Less Wrong Karma Chart Website and let me know what you think or if you run into any issues.