In reply to doc_h:
There isn't a single page on the petzl website (or anywhere I've seen) that'll give you a side by side comparison. Some shops will do so on their website, but it's very high level and only really useful if your chasing after lumens or grams. For a fuller comparison you really need to read up on each one. Unfortunately, a lot of online shops apply their own tags to torches for some reason (hence TacTikka 200 etc) which complicates matters when trying to buy!
Best place to see the differences is the petzl website where they have all the details on all the current models, and good explanations of what it all means (worth reading up on what their constant lighting tag means for example otherwise their torch performances look rubbish compared to competitors)!
There was an article on here at one point as well comparing higher end torches, and a good follow up article by petzl on their reactive series - worth a quick search of the articles page for those.
Unfortunately it just takes time to read up on the different brands and models and decide what features you like best and hence the model.
For what it's worth, I really rate the MYO range from petzl for general mountaineering and have the old TIKKA RXP (superceded by the reactik range) that I use for running and increasingly as my primary torch. Both would be good replacements for your tikka, though the reactiks are lithium ion batteries (optional crossover kit for AAA, or spare Li-ion batteries available). Personally, I've never had a problem with using them for weekend missions, or longer trips where I'm not expecting to use them for long durations each day.
Cheers and happy torch hunting!
Stu