Care to elaborate? Sharing your insight could be beneficial to others as to why you would pay for TextMate and not BBEdit. Just saying you're a fan of one and not another doesn't really help anything.
Well, TextMate looks very innocent, because the UI is very minimalistic. However, once you understand the elegant implementation of tab triggers and the very smart syntax highlighting (which is actually useful to look for errors) and such, you'll love it. It's completely customizable via bundles and you can use several of them at the same time: for instance, I usually use the LaTeX bundle to write my code, the TODO bundle to make todo lists on the fly (that TextMate can extract and display in an extra window) and the git bundle to manage versions and branches of my document. If you prefer subversion, there's obviously a bundle for that as well.
You can customize bundles and program bundles yourself if you want to -- and bundles are open source, you do not need to pay for them. Bundles are
extremely powerful if programmed properly. For instance, if I add a reference in my tex code, \ref{}, and I type the first few letters of the label I have in mind, the LaTeX bundle in TextMate generates a list of possible matches. This means, it scans all other files for references and pattern matches. If I type \cite{} to add a citation and I enter parts of the title, name or other things that are not necessarily in the label itself, TextMate will look for possible matches in my bibtex file and offer choices. Once I choose the one I want, it automatically replaces whatever I have typed with the correct label. I have never, ever seen an editor do something like that before. Now I'm used to it.
While writing code, TextMate recognizes sections that belong together and adds fold marks. I can fold entire subsections or long formulas at the push a mouse button (I could also use F2).
TextMate also offers file management via projects (which integrates with git and subversion by coloring files that have changed) and -- for some bundles -- also previews. As I understand, only BBEdit 9 has gotten this feature. Projects were actually the reason why I switched from free editors (TeXShop for LaTeX and SubEthaEdit/TextWrangler for other stuff) to TextMate: managing TeX projects and webpages is easy now.
The html bundle uses WebKit to render previews. It doesn't save you from opening in different browsers just to check if the code works there as well, but it's a very good start.
I think I paid 35 for it, although it has become more expensive in the meantime. Now it costs 49 -- which is still less than half of what you currently pay for BBEdit. (At one point, I remember that barebones wanted
close to $200 for their editor.)
I have tried BBEdit several times (the first time on OS 8.5 or 8.6, I believe), but I found it to be clunky. It still has the flair of a classic app, although that clearly isn't a criterion. BBEdit is better when you have to open files whose size is more than 500 kB or 1 MB. TextMate gets a bit slow -- but in that case, I open the file with vim on the command line.
To me, BBEdit misses many critical features (bundles, autocompletion) and a nice user interface. Plus, it's too expensive for my taste.
