From the announcement:
"""Performance: Overall performance is fine, but there are still edge-cases that we haven’t looked into, for example the long lines issue which also exists in 1.x or opening files that exhaust TextMate’s memory space."""
So, the same performance re: long lines and long files as 1.x.
And here I thought that the lack of new features meant that at least the core engine was re-worked. Now, it seems like there just wasn't much done at all, backend or front-end wise.
The list here couldn't be more basic or boring: http://macromates.com/changes
Here's what I'd like to see, minimum:
1) SCM integration
2) Split panes
3) Better fuzzy search
4) Robust long line handling
5) Robust long file handling
6) Improved extensibility esp. with re: build systems\
7) Robust auto-completion
8) Better project handling features