According to the existing immigration rules & regulations, can American citizens still apply for siblings to get green card?

Yes, the F4 category for siblings still exists. The wait will probably be around 12-15 years. She will not be automatically denied a visitor's visa...

I-551 still ok to travel with?

Please refer to the following USCIS publication: http://www.uscis.gov/sites/default/files/files/pressrelease/I551ReplacementQA082207.pdf

When are removal proceedings issued after an I-130 denial ?

Notice to Appear will be issued, unless there is an oversight. It is impossible to tell how soon it will be issued.

Fiancé visa and I-601

Is is impossible to give you an idea about your chances to succeed without a thorough interview. Waiver cases are very hard to win, and every...

Would I be eligible for H1B cap exemption?

Yes, you should be able to use the first petition.

You may file an appeal on Form I-290B, Notice of Appeal or Motion, within 30 days of the date of the USCIS decision. If the time for appeal has...

Should I send bonafide of marriage letters to NVC?

You should strictly follow the instructions from the National Visa Center.

Inviting family to visit united States.

Your mother should contact the local US consulate to request a B2 visa. No formal invitation is necessary. Your mother has the burden to show that...

I-130 has been in initial review state for over 7months, it was transferred from national benefit center to California

It is very common for I-130 petitions filed for parents of US citizens, for example, to take 9-10 months to get approval. Some petitions are being...

Can immigration officer deny you of Citizenship if you did not notify them of change of address?

You would have to convince the immigration officer that you maintained your California address, and never intended to relinquish it. Hiring an...