The 3.5 release comes with lot of new strings, so it's some work to get to 100%. However some translators have already managed this and we currently have five translations on 100%:
- English (Great Britain)
There are few which are really close to 100% and I hope they will get there soon:
Just on next level is Czech, where I'm progressing quite slowly and would welcome help :-).
Was your language not mentioned? It's now perfect time to contribute to it.