Site Validation

I just did a W3 validation on my site running xf 1.1 BETA5 and came up with just over 50 errors so thought I had better fix these.

However, as a benchmark I did a validation on and it came up with 23 errors and 4 warnings.

Obviously I have 30 odd more errors to fix but am curious as to the other 23 ones that XF itself has brought up.
Thanks, just worried about Google ranking and trying to help it along by making things posted in those other threads, the site works and works well so ???????