I like the phallic one. The elements are blended into one visual object, as it should be in a logo, and there's a feeling of movement, of informality, and of fun.
The monochrome gray is boring, but it's easy to experiment with different color schemes. Since the letters are all simple shapes with broad strokes, you might even try filling some of them with photos or artwork that articulate the blogger's theme.

The Diamond logo is clever (has the second message "I Do Brighton"). If you go in this direction, ditch the diamond shape and the writing hand, as they're kinda superfluous and distract from the second message. You can easily make it more whimsical by choosing a different typeface.

I'm with blitzen.

Terrific input thankyou. Such a great place for getting feedback.

I did a couple more as per suggested - do you think it works?

I don't think that you want such a vertical mark for primarily web use. Something horizontal usually works best for a website identity. I think the 'I do' concept is solid, if a little vague ('I do" could suggest weddings for example), but the name is vague to begin with.

I like the very first concept you posted, although it would need some work. In the more recent "I do" batch, I like #1 the best, although the line spacing bothers me a bit (I like to see lines 1 and 2 closer together, but the ascender on the "d" creates a problem). Don't think I'd agree with comment about being too vertical; that one looks more squarish to me than vertical.

What I meant by too vertical is really not horizontal enough (think: flickr, facebook, google, yahoo, etc.).

I'd see how an all-caps version looks using Sauna (or Rockwell or any other face you're considering) this will help you square up the type and avoid the weird gaps. If you do stick to lowercase, capitalize the "i"

I do Brighton?? Like I have sex with Brighton????