a young, freshy design company (a models "book" company, print ads, web design and so on). called "M&M Studio". this is the current logo, what do you think? how can i improve it but still keep the spirit? 

Take a look at http://www.dotcomlogotypes.com/ for inspiration ;-)
"you are all right. but i'm kinda lack of ideas. how about this design, looks any better? "
Not to be harsh, but no. It looks worse.
Tell us more about the firm. What kind of modelling? Who hires them? Who models for them? What did the worm originally refer to? Anything? What city is it in? Etc.
I think you are trying too hard here. Keep it simple. Find a really nice typeface and work with that as the foundation.
Take the advice of the Orange Italic boys and stick closer to fashion convention for your type. Thus far, you're missing the mark. Although, I'm not sure I can recommend dropping $1500 for the Luxury collection specifically.
Your versions in post 477 are better by far, but remind me of Crate & Barrel and a 'modern' style that's not as contemporary anymore. Without more information than I have, I'd go with elegant and sophisticated, rather than fun or modernist.
PS: Avoid the ampersand, otherwise you might get a call from a certain candy company...
Chris, the versions in 477 aren't the OP's. I actually like the very last one (the 3 hump m), but I agree that the others are too Crate & Barrel.
As for the ampersand, I think you'd be fine if 1) the ampersand were large and decorative, and 2) the M's were uppercase (since the candy is lowercase).
Besides, there are already a number of M&M's out there:
www.mmmeatshops.com/
www.mandmsports.com/
www.mmhair.co.uk/ (with an interesting ampersand)
www.mnmonline.com/ (ouch!)
www.mmwatersports.com/
The logo on your site is the best version you have so far.
I am guessing from your domain name that you are based in Italy. I am not sure what trends are popular in Italy these days (I am mostly familiar with 2 type designers work from there-Fabrizio Schiavi (FSD fonts), and Claudio Piccinini) but
for some reason your work looks more Eastern European. I say this because I worked with a sign company from Romania for a couple of years, and the stretched type is very common there. Your work shown here is dated looking, it appears to be "new wave" 80's / early 90's looking. I do not known if this is intentional (as in "retro") but in my opinon it is not working at all. The type you have currrently on your site, although perhaps not refined, is
superior to the stretched work show here. For critique
you have come to the right place, so stick with some of the advice and keep going. Start with concept, then fonts, then legibility, then refine concept, proportion.....
another site to get perhaps an oblique look at the fashion world:
http://www.hintmag.com/
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