Submit Button Has Changed

The only form I noticed was on the Registration page and I did see a Submit button... I have attached a screenshot:

http://grab.by/6uJy

If you can be more specific with your request, which form, what page, what browser/operating system, etc.

In any event it is most likely going to be CSS related.

The Thesis specific background image was removed in the last version so it didn't cause problems with non-Thesis users. You'll have to add that yourself if you want to keep it.

Other than the background image, the other styles should remain the same. We did get more granular with the Thesis CSS specificity, again to prevent interfering with other non-Thesis themes. The updated button style is below

body.custom #container #page #content_box .post_box .format_text .gform_footer input.button {border-color:#CCC #999 #999 #CCC; border-right:3px double #999; border-style:double; border-width:3px; color:#111111; background-color:#E3E3E3; cursor:pointer; font-weight:bold; overflow:visible; width:auto !important; font-family: Georgia, "Times New Roman", Times, serif; font-size:1.143em; padding:0.313em 0.25em}

Here's a screenshot of Gravity Forms 1.4.2 running in a default install of Thesis 1.8. You'll see that the default styles still work fine.

If you've updated your theme and the structure has changed, then you'll have to adjust the inheritance to match the structure of your theme.